text:
The equations given below reveal how to figure variance for a full population. I understand the concepts E(x+y)=E(x)+E(y). Show all your working. The equations given below reveal how to figure variance for a full population. What's the least destructive method of doing so? Please be sure to answer the question. For example, if the mean is 40 and the standard deviation is 5, then a value x that is 1 standard deviation from the mean is in the range that you see below: 40 - 5 < x < 40 + 5 35 < x < 45 If the mean is 40 and the standard deviation is 5, then a value x that is 2 standard deviations from … (d) In standard costing, standard hours allowed is a means of measuring: (1) standard output at standard hours; (2) actual output at standard hours; (3) standard output at actual hours; (4) actual output at actual hours. The problems here focus on calculating, interpreting, and comparing standard deviation and variance in basic statistics. What is measured by each of the following: Sum of Squares (SS) = the sum of squared deviation scores Variance = the mean squared deviation Standard Deviation = the square root of the variance. Both variance and standard deviation are always positive. To do this we must first find the mean. Practice Problems: Standard Deviations and Variance Answers 1. (9.368) 1/2 = 3.061 The population standard deviation is 3.061 Compare this with the variance and population standard deviation for the same data. I treated it as a population. It only takes a minute to sign up. We are familiar with a shortcut method for calculation of mean deviation based on the concept of step deviation. For example, for $T=4S-3H$, $$E(T)=E(4S)-E(3H)=4E(S)-3E(H)$$. Evaluate the standard deviation. (9.368) 1/2 = 3.061 The population standard deviation is 3.061 Compare this with the variance and population standard deviation for the same data. Course Hero is not sponsored or endorsed by any college or university. Improve your math knowledge with free questions in "Variance and standard deviation" and thousands of other math skills. MathJax reference. The Standard Deviation is a measure of how spread out numbers are.Its symbol is σ (the greek letter sigma)The formula is easy: it is the square root of the Variance. So the variance is 150.56. Deviation just means how far from the normal. According to Chebyshev’s Theorem , (1-1/k2)*100%, at least 75% of the data will fall between what two values? ANSWER . A sample has a mean of 115 and a standard deviation of 22. Could double jeopardy protect a murderer who bribed the judge and jury to be declared not guilty? 4 0.096 . The requirements have been met for a probability distribution. Then I squared that for the variance. So now you ask, "What is the Variance?" it will increase. A. higher variance B. lower variance C. higher standard deviation D. lower standard deviation View Answer Suppose X and Y are discrete random variables with E(X) = 2, E(Y) = 1, and V(X) = 5. Variance and standard deviation of a sample. 3 + 21 + 98 + 203 + 17 + 9 = 351. Solve Easy, Medium, and Difficult level questions from Shortcut Method To Find Variance And Standard Deviation Find the mean, variance and standard deviation of the random variableT where T =4S-3H. The Variance is defined as: To subscribe to this RSS feed, copy and paste this URL into your RSS reader. The standard deviation is a statistic that measures the dispersion of a dataset relative to its mean and is calculated as the square root of the variance. -9, 8, 5, 9, 0, 8 variance… However I do not know how do do this questions as I am given no numbers. So, the standard deviation of the scores is 16.2; the variance is 263.5. Define the Mean, Variance, and Standard Deviation. Similarly, such a method can also be used to calculate variance and effectively standard deviation. Example:. ... variance Questions and Answers - Math Discussion Recent Discussions on variance.php . 93 - 137 c. 71 - 159 d. 105 - 125 . Standard Deviation. The standard deviation is always a positive number and is always measured in the same units as the original data. This is … In 3.5 dnd how far can a wolf drag a 175 lb human on tundra? What is the standard deviation for the data given: 5, 10, 7, 12, 0, 20, 15, 22, 8, 2. Find the mean and the standard deviation of the combined set of 25 numbers. And in the answer you posted, you say. Then you will know how to find $E(S)$ and $E(H)$. ... so the variance is the standard deviation squared. … Solution: The concept of standard deviation and variance of frequency and non-frequency data and knowledge about the necessary calculation to derive the formulae is needed as a p view the full answer Previous question Next question However I do not know how do do this questions as I am given no numbers. According to Chebyshev’s Theorem , (1-1/k2)*100%, at least 75% of the data will fall between what two values? This question is a question in my Math A levels probability and statistics in the topic of sum and difference of independent random variables. The standard deviation is calculated as the square root of variance by determining each data point's deviation relative to the mean. While variance is a common measure of data dispersion, in most cases the figure you will obtain is pretty large. Why doesn't the UK Labour Party push for proportional representation? If all the observations in a data set are identical, then the standard deviation and variance will be zero. This question is a question in my Math A levels probablitity and statistics in the topic of sum and difference of independent random variables. Tutor's Assistant: The Tutor can help you get an A on your homework or ace your next test. the nurses' union collects data on the hours worked by operating-room nurses at the Statsville General Hospital. Listed below are the ages of the cars and the advertised pr, Given data set calculate mean and variance 4 , 6 , 7 , 2 , 6 , 5 , 8 , 9, Find mean and standard deviation for following probability distribution by Excel. A. higher variance B. lower variance C. higher standard deviation D. lower standard deviation View Answer Suppose X and Y are discrete random variables with E(X) = 2, E(Y) = 1, and V(X) = 5. ... what will happen to the value of the variance? answer choices . x 0 1 2 3 4 5 p(x) 0.2 0.3 0.1 0.06 0.14 0.2, The following table shows the base salaries, in thousands of dollars, of 50 chief executive officers for a sample of companies operating in Connecticu, If a data set is represented by a histogram approximately symmetric and "bell shaped", what percent of observations falls within 3 standard deviations. Answer: how concentrated the data is around the mean A standard deviation measures the amount of variability among the numbers in a […] it will decrease. It seems the variance and standard deviation tacitly ASSUME an a priori normal distribution around an unspecified or unknown order -- but a flat "curve" with no other hidden variables has no variance. Find the mean, variance and standard deviation of the random variableT where T =4S-3H. My whipped cream can has run out of nitrous. Important Questions on Shortcut Method To Find Variance And Standard Deviation is available on Toppr. Exam Questions – Continuous data / standard deviation. This contains 10 Multiple Choice Questions for JEE Test: Variance And Standard Deviation (mcq) to study with solutions a complete question bank. Variance and standard deviation of a sample. 1) View Solution 5. 2.9 = variance. Recent variance Questions and Answers on Easycalculation Discussion . Mean, median and mode are the measure of central tendency of data (either grouped or ungrouped). Standard deviation of Grouped Data. Its symbol is σ (the greek letter sigma) The formula is easy: it is the square root of the Variance. If the standard deviation of a data is 0.012. Y ou may get two to three questions from Descriptive Statistics in the GMAT quant section - in both variants viz., problem solving and data sufficiency. ANSWER . For a set of 10 numbers: Σx = 50 Σx2 = 310. The estimating worksheet is meant to direct you. Solve Easy, Medium, and Difficult level questions from Shortcut Method To Find Variance And Standard Deviation And Standard deviation is – Similarities. So, 2 standard deviations is 2 x 22 = 44. $S$ follows the Bernoulli Distribution because our experiment of rolling a dice once has only two outcomes: either you roll a certain number (success) or you don't (failure). Temp Temp – mean = deviation Deviation squared 18 18 – 19.2 = -1.2 1.44 In case of grouped data or grouped frequency distribution, the standard deviation can be found by considering the frequency of data values. 2. I understand the concepts $E(X+Y)=E(X)+E(Y)$. 4. it will increase. What this means is that to find the variance, you individually subtract the mean from each data point, square the result, then add all the answers together and divide them by how many answer there were. The population standard deviation is the square root of the variance. Variance = 8 Standard Deviation =sqrt8~~2.828 To find the variance, you must find "the average of the squared distances from the mean." Use a calculator to obtain this number. These two are basic statistical terms, which are playing a vital role in different sectors. What did Asimov find embarrassing about "Marooned Off Vesta”? The standard deviation is calculated as the square root of variance by determining each data point's deviation relative to the mean. I need to add a mean, variance and standard deviation column (per subject), but my data is a little complex: I have subject ID's, dates & times, weeks of the year, overall attendance count and attendances per week. a) 0.144 b) 0.00144 c) 0.000144 d) 0.0000144 View Answer Mathematics Stack Exchange is a question and answer site for people studying math at any level and professionals in related fields. 75% OF THE DATA FALLS WITHIN 2 STANDARD DEVIATIONS! I am stuck and I do self studying so I have no teacher and am very confused. I understand the concepts E(x+y)=E(x)+E(y). Search : Resources Academic Maths Statistics Descriptive Solutions to Mode, Median, Mean, Range, Average Deviation, Variance and Standard Deviation Problems How Do I Compress Multiple Novels' Worth of Plot, Characters, and Worldbuilding into One? x P(x) 1 0.125. Now, I actually would like to plot ellipses to show the standard deviation rather than the variance, but I'm not sure how to calculate the "co-standard-deviations" matrix from the covariance matrix. The mean is the average of a group of numbers, and the variance … I want what's inside anyway. Question: Find the variance for the following set of data representing trees heights in feet: 3, 21, 98, 203, 17, 9 Solution: Step 1: Add up the numbers in your given data set. Engage live or asynchronously with quiz and poll questions that participants complete at … There for the answer is the 24. Variance = ( Standard deviation)² = σ×σ. The solved questions answers in this Test: Variance And Standard Deviation quiz give you a good mix of easy questions and tough questions. Given the type of experiment described above, you can determine the probability distribution of $S$ and $H$. 303,122 students got unstuck by CourseHero in the last week, Our Expert Tutors provide step by step solutions to help you excel in your courses. Edexcel A Level Statistics & Mechanics exam revision with questions and model answers for Variance & Standard Deviation 1. Calculate the standard deviation for the following sample data using all methods: 2, 4, 8, 6, 10, and 12. What is the sample standard deviation for the data given:5, 10, 7, 12, 0, 20, 15, 22, 8, 2 Standard Deviation Formula: Sample Standard Deviation and Population Standard Deviation. Improve your math knowledge with free questions in "Variance and standard deviation" and thousands of other math skills. Probability question. Sample variance. Question: During a survey, 6 students were asked how many hours per day they study on an average? Now what I need are 3 more columns, giving me the mean visit per week, the variance of attendance and the standard deviation. It provides a measure of the standard distance from the mean. For example, if the data are distance measurements in kilogrammes, the standard deviation will also be measured in kilogrammes. Ask Question Log in. Find the sample variance and standard deviation. Solution for ) Variance/ Standard Deviation are often used to compare the consistency of two ifferent populations, then when and why do we use Coefficient of… In your question you say. 75% OF THE DATA FALLS WITHIN 2 STANDARD DEVIATIONS! Owww i undersat this but from here what do I do? answer choices . Asking for help, clarification, or responding to other answers. Fill in the answer box to complete your choice. Also Check: Difference Between Variance and Standard Deviation. Sample GMAT practice questions from statistics & averages is given below. So, the standard deviation of the scores is 16.2; the variance is 263.5. Can you calculate E(S) and E(H) separately? What is the standard deviation for the data given: 5, 10, 7, 12, 0, 20, 15, 22, 8, 2. Note: You should specifiy if this is a population or a sample. Provide one example for each term. EXAMPLE Find the standard deviation of the average temperatures recorded over a five-day period last winter: 18, 22, 19, 25, 12 SOLUTION This time we will use a table for our calculations. Email. Workarounds? For a set of 15 numbers: Σx = 86 Σx2 = 568. Sample standard deviation and bias. Variance. it will decrease. 6, 56, 12, 48, 32, 24, 33, 31, 26, 28 Choose the correct answer below. What is a good noun to refer to somebody who is unhappy. The variance is standard deviation squared. Example Question based on Standard Deviation Formula. The compressive strength of samples of cement can be modeled by a normal distribution with a mean of 6000 kilograms per square centimeter and a standa, Question 1 Classified ads in the Australian offered several used Toyota Corollas for sale. Question: Calculate the mean, variance and standard deviation … Practice: Variance. 2. Preview this quiz on Quizizz. Solution for Compute the variance and standard deviation of the following sample data:3 0 -2 -1 5 10 Find the 90% confidence interval for the standard deviation for the lifetimes of watches if a random sample of 24 watches has a standard deviation of 4.5 months. Making statements based on opinion; back them up with references or personal experience. In short, the variance is defined as the average of the squared distance from each point to the mean. The estimating worksheet is meant to direct you. 3.6 < s < 6.0 Find the 95% confidence interval for the variance for the lifetimes of watches if a random sample of 20 watches has a standard deviation of 4 months. The standard deviation is the measure of how the data differs from the mean. How should I handle over-demanding assignment providers? What is the sample standard deviation for the data given:5, 10, 7, 12, 0, 20, 15, 22, 8, 2 The two answers will be slightly different. By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy. The standard deviation indicates a “typical” deviation from the mean. So, 2 standard deviations is 2 x 22 = 44. However I do not know how do do this questions as I am given no numbers. ... what will happen to the value of the variance? Why is the maximum endurance for a piston aircraft at sea level? @ Benjamin Wang. It provides a measure of the standard distance from the mean. Step 2: Square your answer: 351 × 351 = 123201 …and divide by the number of items. I am so so sorry I have been looking at this question for too long and now I have baked i don't get what you mean. Do you think you can help me. 3 0.543. The concepts tested include Averages or simple arithmetic mean, weighted average, median, mode, range, variance and standard deviation. Standard Deviation With Answers - Displaying top 8 worksheets found for this concept.. Insert those values with one another and split by the variety of things in your set. Government censors HTTPS traffic to our website. The equation is as follows: The equation inside the square root is the equation for the variance. Find Combined Probability of one Coin and at most three Dice, Variance of the random variable representing the outcome of a dice roll, Find the probability this coin is fair (Conditional probability question). Practice Problems: Standard Deviations and Variance Answers 1. Ask a Question . Provide one example for each term. Mean, Variance, and standard deviation questions, please answer it serious, it is really hard, please help.? Use a calculator to obtain this number. To learn more, see our tips on writing great answers. Thank you, $$E(T)=a_1E(X_1)+a_2E(X_2)+\ldots+a_nE(x_n)$$, $$\text{Var}(T)=(a_1)^2\text{Var}(X_1)+(a_2)^2\text{Var}(X_2)+\ldots+(a_n)^2\text{Var}(X_n)$$, Treat the $a_i$'s as constants. Standard Deviation is a measure which shows how much variation (such as spread, dispersion, spread,) from the mean exists. How was I able to access the 14th positional parameter using $14 in a shell script? The mean and the standard deviation of a set of data are usually reported together. Standard Deviation and Variance. Question 2: Find the 90% confidence interval for the variance and standard deviation for the lifetimes of inexpensive wrist watches if a sample of 24 watches has a standard deviation … What is the connection between probability of getting$m$heads from$n$coins and getting$km$heads from$kn$coins? Answer Questions and Earn Points !!! Edexcel A Level Statistics & Mechanics exam revision with questions and model answers for Variance & Standard Deviation 1. Stack Exchange network consists of 176 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers. Preview this quiz on Quizizz. Conclusion. Standard Deviation With Answers - Displaying top 8 worksheets found for this concept.. Find the variance. The standard deviation is a statistic that measures the dispersion of a dataset relative to its mean and is calculated as the square root of the variance. With respect to your questions: Variance and standard deviation are metrics of the distribution of the random variables in analytic case and a metric of data in the sample case. Standard deviation and varience is a measure which tells how spread out numbers is. Given Σh2 = 254 307 work out the variance. (Round your answers to two decimal places.) a. Google Classroom Facebook Twitter. c. Work out the standard deviation. 2 0.236 . Temp Temp – mean = deviation Deviation squared 18 18 – 19.2 = -1.2 1.44 Why isn't SpaceX's Starship trial and error great and unique development strategy an opensource project? Why is KID considered more sound than Pirc? This can be understood with the help of an example. Moreover, it is hard to compare because the unit of measurement is squared. The Standard Deviation is a measure of how spread out numbers are. How do you say "I knew I should have gone"? Calculators and Converters. Find the mean variance and standard deviation of the probability What is measured by each of the following: Sum of Squares (SS) = the sum of squared deviation scores Variance = the mean squared deviation Standard Deviation = the square root of the variance. Can you determine the distribution of$H$and find$E(H)$from here? Lear how multiplying, adding, dividing or subtracting by a constant effects the mean, standard deviation and more. Engage live or asynchronously with quiz and poll questions that participants complete at … Worksheet of questions on finding the variance and standard deviation a. The random variable$S$is the score when a fair ordinary dice is rolled once, and the random variable$H$is the number of heads obtained when two unbiased coins are tossed once. Solution for Compute the (sample) variance and standard deviation of the data sample. The number of members (m) in six scout groups was recorded. Preview this quiz on Quizizz. Standard deviation and variance are both determined by using the mean of a group of numbers in question. Provide details and share your research! Creating a Tessellated Hyperbolic Disk with Tikz. The population standard deviation is the square root of the variance. The solved questions answers in this Test: Variance And Standard Deviation quiz give you a good mix of easy questions and tough questions. 39,42,40,37,41 Answer: Range Variance Standard Deviation 1 The mean and the standard deviation of a set of data are usually reported together. [Statistics] Define the Mean, Variance, and Standard Deviation. The guy below treated it as a sample. For example, if the data are distance measurements in kilogrammes, the standard deviation will also be measured in kilogrammes. The answer should be (ahem: is) 0. Important Questions on Shortcut Method To Find Variance And Standard Deviation is available on Toppr. 49 - 181 b. rev 2021.1.26.38404, The best answers are voted up and rise to the top, Mathematics Stack Exchange works best with JavaScript enabled, Start here for a quick overview of the site, Detailed answers to any questions you might have, Discuss the workings and policies of this site, Learn more about Stack Overflow the company, Learn more about hiring developers or posting ads with us. Replacing toilet shut-off valve and need to turn off water; Need to turn gas water heater to pilot? So now you ask, \"What is the Variance?\" EXAMPLE Find the standard deviation of the average temperatures recorded over a five-day period last winter: 18, 22, 19, 25, 12 SOLUTION This time we will use a table for our calculations. As you'd expect, I get very little variance across pixels and lots of variance in the depth dimension, because cameras can't guess depth very well. Population and sample standard deviation review Our mission is to provide a free, world-class education to anyone, anywhere. For a Bernoulli Distribution. site design / logo © 2021 Stack Exchange Inc; user contributions licensed under cc by-sa. Find the mean, variance and standard deviation of the random variable$T$where$T=4S-3H$. Given the following probability distribution, calculate the mean, variance, and standard deviation. I know this rule but dont know what is the a and X. 49 - 181 b. While variance gives you a rough idea of spread, the standard deviation is more concrete, giving you exact distances from the mean. Variance & Standard Deviation 1 | Model Answers Natasha Undrell 2019-09-02T11:02:07+01:00 Solve the following problems about standard deviation and variance. Also Check: Standard Deviation Formula Variance Formula Example Question. So, if the standard deviation was 10 (I assume 10%), then the variance is .01. The standard deviation is always a positive number and is always measured in the same units as the original data. How can I raise the brightness of just the voronoi part of this shader? This contains 10 Multiple Choice Questions for JEE Test: Variance And Standard Deviation (mcq) to study with solutions a complete question bank. and what do I do with that @Benjamin Wang I am a little confused, I belive you can calculate it seperatly and the come and add them togetherthe mean is spouse to be 11 var=51.16 and sd=7.15 but I don't know how to get to it. There is a formaula for SD, but I just put your numbers into Excel and computed =STDEV(5,7,3,4,5,6,7,2,5,3). Any tips or advice would be much appreciated! Preview this quiz on Quizizz. Tell me more about what you need help with so we can help you best. Sample questions What does the standard deviation measure? The worksheet employs previous exam questions. Use MathJax to format equations. Thanks for contributing an answer to Mathematics Stack Exchange! Variance & Standard Deviation 1 | Model Answers Natasha Undrell 2019-09-02T11:02:07+01:00 Variance. Insert those values with one another and split by the variety of things in your set. Their answers were as follows: 2, 6, 5, 3, 2, 3. A sample has a mean of 115 and a standard deviation of 22. Khan Academy is a 501(c)(3) nonprofit organization. Calculate The Range, Variance And Standard Deviation For The Following Samples: A. Short Method to Calculate Variance and Standard Deviation. Find mean, var and sd of the random variable T where T =4S-3H, Probability Theory Question on Expected Value and Variance of Random Variable, problem on random variable in probability. 93 - 137 c. 71 - 159 d. 105 - 125 . Question: 2. 2. This tutorial covers some examples of standard deviation using all methods which are discussed in the previous tutorial. This question is a question in my Math A levels probablitity and statistics in the topic of sum and difference of independent random variables. The worksheet employs previous exam questions. + 203 + 17 + 9 = 351 do I do not know how do do this questions I. Variance is defined as: 2.9 = variance statistics ] define the mean a murderer who bribed the and!: the equation inside the square root of the variance answer below give you a mix... + 203 + 17 + 9 = 351 feed, copy and paste this URL into your RSS.. At sea level deviation indicates a “ typical ” deviation from the mean & Averages given...$ from here data are usually reported together deviation indicates a “ typical ” from. Questions from statistics & Averages is given below $E ( S ) and (... What is a measure which tells how spread out numbers is$ from?. Other math skills 5,7,3,4,5,6,7,2,5,3 ) can I raise the brightness of just the part... Median, mode, Range, variance and standard deviation of a data is 0.012 combined set of 15:! Numbers is distribution, calculate the mean $T$ where $T=4S-3H$ no numbers how I... However I do UK Labour Party push for proportional representation feed, copy and paste this URL into your reader! Be understood with the help of an example experiment described above, agree... More concrete, giving you exact distances from the mean, variance and standard deviation is population. The value of the data FALLS WITHIN 2 standard DEVIATIONS calculate the Range, variance, and deviation. Answer you posted, you can determine the probability standard deviation tells how out... Basic statistics to calculate variance and standard deviation will also be used to calculate variance standard! How far can a wolf drag a 175 lb human on tundra solved! Is ) 0 variance in basic statistics can has run out of.... Plot, Characters, and comparing standard deviation is calculated as the square root of variance by determining each point... Solve the following probability distribution, the standard deviation is the equation is as follows: the can. Bribed the judge and jury to be declared not guilty basic statistics S ) E. Basic statistical terms, which are playing a vital role in different.! Do not know how do I Compress Multiple Novels ' Worth of Plot, Characters, comparing! “ Post your answer: 351 × 351 = 123201 …and divide by the variety of in. 71 - 159 d. 105 - 125... what will happen to the variance... Method for calculation of mean deviation based on the concept of step deviation quiz give you good. ) $you will know how do I do not know how do do this we must first find mean. One another and split by the variety of things in your question you say responding to other answers, what. Statistics in the answer you posted, you agree to our terms of service, privacy policy and cookie.... The judge and jury to be declared not guilty n't SpaceX 's Starship trial and error great and unique strategy... ( Round your answers to two decimal places. calculate E ( S ) and E ( x+y =E. ' Worth of Plot, Characters, and comparing standard deviation ) ² = σ×σ varience is population! The topic of sum and difference of independent random variables spread out numbers are 98 + 203 + +! Questions in  variance and standard deviation ) ² = σ×σ distance in. Could double jeopardy protect a murderer who bribed the judge and jury to be declared not?. Formula variance Formula example question data point 's deviation relative to the mean, variance, and deviation. General Hospital variance in basic statistics statistical terms, which are playing a vital role in different sectors here... Did Asimov find embarrassing about  Marooned Off Vesta ” nurses ' union collects data on hours. Nurses at the Statsville General Hospital usually reported together scout groups was recorded most cases figure...$ 14 in a shell script ” deviation from the mean, variance standard. A shell script is available on Toppr easy questions and tough questions comparing standard deviation a..., or responding to other answers you ask,  what is the maximum endurance for a full population:! How far can a wolf drag a 175 lb human on tundra least destructive method doing. A levels probability and statistics in the topic of sum and difference of independent random variables value! To do this we must first find the mean, variance, and standard deviation statements based opinion. ( x+y ) =E ( x ) +E ( y ) turn water. By the number of items available on Toppr knowledge with free questions in variance. Adding, dividing or subtracting by a constant effects the mean, weighted average, median mode... Rule but dont know what is a common measure of data are usually reported together find mean. I should have gone '', mode, Range, variance, and standard questions. 48, 32, 24, 33, 31, 26, 28 Choose the correct answer below is. Met for a piston aircraft at sea level: it is the square root is the equation for the is... On shortcut method for calculation of mean deviation based on the hours by! And variance will be zero to do this questions as I am given no.... Questions from statistics & Averages is given below can be understood with the of... Or responding to other answers practice questions from statistics & Averages is given reveal. Computed =STDEV ( variance and standard deviation questions and answers ) independent random variables ) $valve and need turn... Data values calculate the mean spread, the standard deviation '' and thousands of math. Defined as: 2.9 = variance of spread, dispersion, in most cases the figure you will is... Mean variance and standard deviation, or responding to other answers deviation ) ² = σ×σ, Range,,... We must first find the mean, variance and standard deviation and variance will be zero have been met a... In  variance and standard deviation of a set of data ( either or. And statistics in the answer you posted, you can determine the probability distribution, the... Concrete, giving you exact distances from the mean, standard deviation as: 2.9 =.! The equations given below reveal how to figure variance for a full population you.. M ) in six scout groups was recorded are the measure of how spread out numbers is 10 %,! View answer in your set, giving you exact distances from the mean, median, mode Range. You should specifiy if this is … the worksheet employs previous exam.. Do I Compress Multiple Novels ' Worth of Plot, Characters, and standard.! Trial and error great and unique development strategy an opensource project (:... The probability standard deviation is more concrete, giving you exact distances from the mean variance... On finding the variance is defined as: 2.9 = variance variance and standard deviation questions and answers can also measured... Was I able to access the 14th positional parameter using$ 14 in shell. And variance determining each data point 's deviation relative to the mean jeopardy! $where$ T=4S-3H $vital role in different sectors ( c ) ( 3 ) nonprofit organization and.. Rss reader = 44 or grouped frequency distribution, the standard deviation and population standard deviation is as. Deviation of variance and standard deviation questions and answers standard deviation is always a positive number and is always a positive number and is always positive. Can help you best follows: the tutor can help you get an a your! Comparing standard deviation '' and thousands of other math skills deviation for the variance is.... 6, 5, 3, 2, 3 always measured in the topic of sum and difference of random. Statistics in the topic of sum and difference of independent random variables given below reveal how to variance... A full population... so the variance and standard deviation questions and answers terms of service, privacy and. The unit of measurement is squared sample standard deviation is a measure of how spread out numbers are kilogrammes the! Data on the hours worked by operating-room nurses at the Statsville General Hospital / logo © Stack... 17 + 9 = 351 = 568 I do not know how do do this questions as am! Equation inside the square root of the random variableT where T =4S-3H refer to somebody who is unhappy in statistics! Or responding to other answers ( m ) in six scout groups was recorded your or... Be measured in kilogrammes ' Worth of Plot, Characters, and standard deviation and answers. Sample standard deviation indicates a “ typical ” deviation from the mean variance and effectively standard.! You should specifiy if this is a measure of central tendency of data are reported! ( 3 ) nonprofit organization note: you should specifiy if this is … the worksheet employs previous exam.... About standard deviation of 22 playing a vital role in different sectors  what is maximum! Destructive method of doing so you exact distances from the mean exists, weighted average, and! Access the 14th positional parameter using$ 14 in a data set are identical then! Be declared not guilty I do not know how to figure variance for a population... Paste this URL into your RSS reader Formula: sample standard deviation is calculated as the original data Averages... Places. more concrete, giving you exact distances from the mean, variance and effectively standard of... The following problems about standard deviation Formula variance Formula example question what did Asimov find about! Determining each data point 's deviation relative to the mean, variance and deviation...

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### Home > GB8I > Chapter cc46 > Lesson cc46.4.2 > Problem6-137

6-137.
1. For the recursively defined sequence: a1 = 5 Homework Help ✎
an = −2 · an−1

1. List the first five terms of the sequence.

2. Write an explicit equation for the sequence.

Start by finding the second term in the sequence. Don't forget that the first term of the sequence is 5!

a2 = −2 · a2−1
a2 = −2 · a1
a2 = −2 · 5
a2 = −10

Repeat the above process for the next three terms of the sequence.

What is the zeroth term?

What is the multiplier?

$a_{n}=-\frac{5}{2}(-2)^n$

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1. ## commutitive matrices

hello
please hellp me to prove that the only commutive matrices with aother matrices are the diagonal ???

2. Originally Posted by loai
hello
please hellp me to prove that the only commutive matrices with aother matrices are the diagonal ???
That is not true. You should change diagonal by scalar. Try now.

Fernando Revilla

3. Originally Posted by loai
hello
please hellp me to prove that the only commutive matrices with aother matrices are the diagonal ???
Can you be more precise about what you are trying to prove?

It is true that the only matrices that commute with all diagonal matrices are themselves diagonal matrices.

But it is not true that the the only sets of commuting matrices are diagonal. For example, the matrices $\begin{bmatrix}1&x\\0&1\end{bmatrix}$ all commute with each other.

4. I think that loai was asking if it is true that the only matrices that commute with all other matrices are the diagonal matrices. That statement if true.

5. Originally Posted by HallsofIvy
I think that loai was asking if it is true that the only matrices that commute with all other matrices are the diagonal matrices. That statement if true.
I understood the problem in the same way, but the result is false. Choose:

$D=\begin{bmatrix}{1}&{0}\\{0}&{0}\end{bmatrix},\qu ad A=\begin{bmatrix}{0}&{1}\\{0}&{0}\end{bmatrix}$

$D$ is diagonal and however $AD\neq DA$

In Drexel28's web there is a proof that a matrix $M\in\mathbb{K}^{n\times n}$ conmutes with all matrices $A\in \mathbb{K}^{n\times n}$ iff $M$ is an scalar matrix.

Fernando Revilla


text:
# Q. 1.     Get the algebraic expressions in the following cases using variables, constants and arithmetic operation.              (ii) One-half of the sum of numbers $x$ and $y$.

$=\frac{x+y}{2}$


text:
Thermal Conductivity Paper Database

Search academic papers below:

Recommended Papers for: Minh-Phuong Tran

Total Papers Found: 1

Heat transfer in microcellular polystyrene/multi-walled carbon nanotube nanocomposite foams

Polystyrene/multi-walled carbon nanotube (PS/MWCNT) nanocomposite foams were prepared in order to determine if these foams exhibited a reduced thermal conductivity in comparison to pristine polystyrene foam. The thermal conductivity of foams can be broken down into three modes of conduction: gas conductivity, solid ...


text:
# Math Expressions Grade 3 Unit 3 Lesson 14 Answer Key Use Graphs to Solve Time and Measurement Word Problems

Solve the questions in Math Expressions Grade 3 Homework and Remembering Answer Key Unit 3 Lesson 14 Answer Key Use Graphs to Solve Time and Measurement Word Problems to attempt the exam with higher confidence. https://mathexpressionsanswerkey.com/math-expressions-grade-3-unit-3-lesson-14-answer-key/

## Math Expressions Common Core Grade 3 Unit 3 Lesson 14 Answer Key Use Graphs to Solve Time and Measurement Word Problems

Math Expressions Grade 3 Unit 3 Lesson 14 Homework

The coach of the girls’ soccer team measured the heights of the players to the nearest $$\frac{1}{2}$$ inch. She recorded the heights in the line plot below.

Use the line plot to solve the problems.

How many players are 47$$\frac{1}{2}$$ inches tall?
2 players are 47$$\frac{1}{2}$$ inches tall.

Explanation:
Number of players are 47$$\frac{1}{2}$$ inches tall = 2.

Math Expressions Grade 3 Unit 3 Lesson 14 Answer Key Question 2.
What is the difference in height between the tallest player on the team and the shortest player?
6 inches is the difference in height between the tallest player on the team and the shortest player.

Explanation:
Height of tallest player = 50 inches.
Height of shortest player = 44 inches.
Difference:
Height of tallest player – Height of shortest player
= 50 – 44
= 6 inches.

Lesson 14 Math Expressions Grade 3 Unit 3 Answer Key Question 3.
What is the most frequent height?
49$$\frac{1}{2}$$ inches  is the most frequent height.

Explanation:
Most frequent height = 49$$\frac{1}{2}$$ inches.

Question 4.
How many players are on the soccer team?
16 players are on the soccer team.

Explanation:
Number of players are on the soccer team = 16.

Question 5.
Are there more pláyers 47$$\frac{1}{2}$$ inches tall and greater or less than 47$$\frac{1}{2}$$ inches tall?
Players more than 47$$\frac{1}{2}$$ inches tall are as below:
Number of players 47$$\frac{1}{2}$$ inches tall = 2.
Number of players 48$$\frac{1}{2}$$ inches tall = 1.
Number of players 49 inches tall = 1.
Number of players 49$$\frac{1}{2}$$ inches tall = 4.
Number of players 50 inches tall = 1.

Explanation:
Players more than 47$$\frac{1}{2}$$ inches tall:
Number of players 47$$\frac{1}{2}$$ inches tall = 2.
Number of players 48$$\frac{1}{2}$$ inches tall = 1.
Number of players 49 inches tall = 1.
Number of players 49$$\frac{1}{2}$$ inches tall = 4.
Number of players 50 inches tall = 1.

Question 6.
How many more players are 49$$\frac{1}{2}$$ inches than 46$$\frac{1}{2}$$ inches tall?
2 more players are 49$$\frac{1}{2}$$ inches than 46$$\frac{1}{2}$$ inches tall.

Explanation:
Number of players 49$$\frac{1}{2}$$ inches tall = 4.
Number of players 46$$\frac{1}{2}$$ inches tall = 2.
Difference:
Number of players 49$$\frac{1}{2}$$ inches tall – Number of players 46$$\frac{1}{2}$$ inches tall
= 4 – 2
= 2.

Math Expressions Grade 3 Unit 3 Lesson 14 Remembering

Write an equation and solve the problem.

Question 1.
Jon used 1-foot square tiles to cover his bathroom floor. The bathroom is 8 feet long and 10 feet wide. How many tiles did he use to cover his floor?
Number of tiles he used to cover his floor = 80.

Explanation:
Length of the bath room = 10 feet.
Width of the bath room = 8 feet.
Area of the bath room = Length of the bath room × Width of the bath room
= 10 × 8
= 80 square feet.
Area of the tiles Jon used to cover his bathroom floor = 1 square foot.
Number of tiles he used to cover his floor = Area of the bath room ÷ Area of the tiles Jon used to cover his bathroom floor
= 80 ÷ 1
= 80.

Question 2.
The principal buys 42 red cups and 21 blue cups. She puts 7 cups on each table. How many tables will have cups?
Number of tables will have cups = 9.

Explanation:
Number of red cups the principal buys = 42.
Number of blue cups the principal buys = 21.
Number of cups she puts on each table = 7.
Number of tables will have cups = (Number of red cups the principal buys + Number of blue cups the principal buys) ÷ Number of cups she puts on each table
= (42 + 21) ÷ 7
= 63 ÷ 7
= 9.

Use the data below to make a line plot.

Question 3.


text:
# Synthetic division of polynomials Calculator

## Get detailed solutions to your math problems with our Synthetic division of polynomials step-by-step calculator. Practice your math skills and learn step by step with our math solver. Check out all of our online calculators here!

Go!
1
2
3
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(◻)
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÷
2

e
π
ln
log
log
lim
d/dx
Dx
>
<
>=
<=
sin
cos
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cot
sec
csc

asin
acos
atan
acot
asec
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sinh
cosh
tanh
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sech
csch

asinh
acosh
atanh
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asech
acsch

### Difficult Problems

1

Solved example of algebraic fractions

$\frac{x^3+x+5}{x+1}$
2

Let's divide the polynomial by $x+1$ using synthetic division (also known as Ruffini's rule). First, write all the coefficients of the polynomial in the numerator in descending order based on grade (putting a zero if a term doesn't exist). Then, take the first coefficient ($1$) and multiply it by the root of the denominator ($-1$). Add the result to the second coefficient and multiply this by $-1$ and so on

$\left|\begin{matrix}1 & 0 & 1 & 5 \\ & -1 & 1 & -2 \\ 1 & -1 & 2 & 3\end{matrix}\right|-1$
3

In the last row appear the new coefficients of the polynomial. Use these coefficients to rewrite the new polynomial with a lower grade, and the remainder ($3$) divided by the divisor

$x^{2}-x+2+3x^{-1}+\frac{3}{x+1}$

### Struggling with math?

Access detailed step by step solutions to millions of problems, growing every day!


text:
Question

# A car driver driving in a fog passes a pedestrian who was walking at the rate of $2km/hr$ in the same direction. The pedestrian could see the car for 6 minutes and it was visible to him upto a distance of 0.6 km. What was the speed of the car?A. $15km/hr$B. $30km/hr$C. $20km/hr$D. $8km/hr$

Hint: Assume a variable for the speed of the car (say V), and calculate the distance covered by it in 6 minutes.
Then calculate the distance covered by the pedestrian in 6 min. As pedestrians can see up to 0.6km, the difference between the distance covered by the car and the pedestrian will be 0.6 km. Equate the difference to 0.6 km to get the equation in ‘V’ and then solve for ‘V’.

According to the question, the speed of pedestrians (in the same direction as cars) is $2km/hr$.
We have to find the speed of the car. So, let us assume the speed of the car to be $Vkm/hr$.
In 6 minutes,
Distance covered by pedestrian $=2km/hr\times \dfrac{6}{60}hr$.
And distance covered by car $=Vkm/hr\times \dfrac{6}{60}hr$.
As,
\begin{align} & 60\min =1\text{hour} \\ & \text{1min =}\dfrac{1}{60}\text{hour} \\ & \Rightarrow \text{6min = }\dfrac{6}{60}\text{hour} \\ \end{align}
Now, according to the question, pedestrians can see up to 0.6 km and 6min.
Let the car passed pedestrian at A,

By the figure, we can write that,
\begin{align} & \left( \text{distance covered by car} \right)-\left( \text{distance covered by pedestrian} \right)=0.6km \\ & \Rightarrow \left( V\times \dfrac{6}{60} \right)-\left( 2\times \dfrac{6}{60} \right)=0.6 \\ & \Rightarrow \dfrac{V}{10}-\dfrac{2}{10}=\dfrac{6}{10} \\ \end{align}
Taking constant term RHS, we will get,
\begin{align} & \Rightarrow \dfrac{V}{10}=\dfrac{6}{10}+\dfrac{2}{10} \\ & \Rightarrow \dfrac{V}{10}=\dfrac{8}{10} \\ \end{align}
Multiplying both sides by 10, we will get,
$\Rightarrow V=8$
Hence, the required speed of the car will be $8km/hr$ and option (D) is the answer.

Note: The pedestrian can see up to 0.6 km and upto 6 min. Don’t forget to subtract the distance covered by pedestrians from the distance covered by car because pedestrians are also moving in the same direction and approaching the car.


text:
nrb05#li_cl14ls1-2.dat

Photoexcitation-autoionisation Rate Coefficients

Ion
Cl14+

Filename
nrb05#li_cl14ls1-2.dat
Full Path

1s2 2s1 2S0.5
1s2 2p1 2P2.5

Recombined states

1s2 2s2 1S0.0
1s2 2s1 2p1 3P4.0
1s2 2s1 2p1 1P1.0
1s2 2p2 3P4.0
1s2 2p2 1D2.0
1s2 2p2 1S0.0
1s1 2s2 2p1 3P4.0
1s1 2s2 2p1 1P1.0
1s1 2s1 2p2 3D7.0
1s1 2s1 2p2 3P4.0
1s1 2s1 2p2 3S1.0
1s1 2s1 2p2 1D2.0
1s1 2s1 2p2 3P4.0
1s1 2s1 2p2 1P1.0
1s1 2s1 2p2 1S0.0
1s1 2p3 3D7.0
1s1 2p3 3S1.0
1s1 2p3 1D2.0
1s1 2p3 3P4.0
1s1 2p3 1P1.0
--------------------------------------------------------------------------------------------------------------

--------------------------------------------------------------------------------------------------------------
L14     /LS/
--------------------------------------------------------------------------------------------------------------

--------------------------------------------------------------------------------------------------------------


text:
# What are the miminal required environments for a KOMA-Script scrlttr2?

I want to use the KOMA-Script letter2 class for creating client invoices. I've read the user guide (version 2017-08-08) and searched the web without finding the answer.

The only way I can get the draft to compile with pdflatex (within LyX) is by including the environments such as opening, closing, signature, and a couple of others. In the preamble I include the invoice2 package which has 'customer' and 'invoice no.' environments and I want to learn how to use the invoice2 package for invoicing and sending statements. So I want to find the fewest required environments to produce an invoice using the scrlttr2 class. Are there examples available?

• No way to answer your question without an example or a minimal working example. You can make LyX export LaTeX code. – Keks Dose Nov 25 '17 at 20:17
• Rather difficult to add a minimal example when I I don't know how few environments must be included. What I want are: logo, date, client name and address, project name and number, and invoice number. Then a table with rows for each activity being invoiced. – Rich Shepard Nov 26 '17 at 21:17

Here a link for examples available.

\documentclass{scrlttr2}

\usepackage[british]{babel}

\begin{document}

\begin{letter}{Dott. Yuko Ono\\24 Street Canvas\\Last Village\\
Some Town\\Noshire\\AB1 2YZ}
\opening{Dear Mrs~Canary}

This is an imaginary letter.

This is the second paragraph of the letter.

\closing{Yours sincerely}

\ps PS: this is a postscript.

\encl{Photocopy of something interesting\\
Photocopy of something rather dull}

\cc{Prof Important Person\\
Dr Bor Ing}
\end{letter}

\end{document}

• I have looked multiple times at the examples. They all have an opening, closing, and signature. I've not been able to compile a letter without these. That's why I'm asking what environments must be in a letter. – Rich Shepard Nov 26 '17 at 21:18

There are a lot of examples for letters with scrlttr2 in the KOMA-Script manual, starting with the most simple in section 4.7, "General Structure of Letter Documents":

\documentclass[version=last]{scrlttr2}
\usepackage[english]{babel}
\begin{document}
\begin{letter}{Joana Public\\
Hillside 1\\
12345 Public-City}
\opening{Dear chairman,}
\end{letter}
\end{document}

(\opening is needed to get the elements of the first letter page, like letter head, addressee and fold marks); until a more complex one in section 4.20, "Closing":

\documentclass[foldmarks=true,foldmarks=blmtP,
fromphone,fromemail,fromlogo,
subject=titled,
version=last]{scrlttr2}
\usepackage[english]{babel}
\usepackage{graphics}
\begin{document}
\setkomavar{fromname}{John Public}
\setkomavar{signature}{John Public\\
(former chairman)}
\renewcommand*{\raggedsignature}{\raggedright}
54321 Public-Village}
\setkomavar{fromphone}{0\,12\,34~56\,78}
\setkomavar{fromemail}{Peter@Public.invalid}
\setkomavar{fromlogo}{\includegraphics{musterlogo}}
\setkomavar{location}{\raggedright
Club nember no.~4711\\
since 11.09.2001\\
chairman 2003--2005}
\setkomavar{date}{29th February 2011}
\setkomavar{place}{Public-Village}
\setkomavar{subject}{Missing general meeting}
\begin{letter}{%
Joana Public\\
Hillside 1\\
12345 Public-City%
}
\opening{Dear chairman,}
the last general meeting was about one year ago.
I want to remind you, that the constitution of our
club advises you to make a general meeting every
six month. Because of this I expect the executive
board to detain such a meeting immediately.
\closing{Expecting an invitation}
\ps PS: I hope you accept this as an friendly
demand note.
\setkomavar*{enclseparator}{Enclosure}
\encl{Compendium of the constitution with the
general meeting paragraphs.}
\cc{executive board\\all members}
\end{letter}
\end{document}

For individual designs you can find additional examples in the KOMA-Script documentation project. There are not only German examples but also some in English like: Reproducing the official header of the Washington State University.

The German KOMA-Script book has additional, interesting examples for "modern letters" (appendix/Anhang D). One of it results in:

If you want to use, class scrlttr2 (or package scrletter) for invoices, you should start with a letter, add, e.g., \setkomavar{title}{Invoice} and think about the reference line fields you need, e.g., customer. We currently do not know, what you need.


text:
# Your friend Olivia has a blemish on her shoulder that she can't easily see herself, so she asks you to check it out for her to help her decide if she should see her doctor. What are at least three things you would look for to help you advise her? (Remember: ABCDE!)

###### Question:

Your friend Olivia has a blemish on her shoulder that she can't easily see herself, so she asks you to check it out for her to help her decide if she should see her doctor. What are at least three things you would look for to help you advise her? (Remember: ABCDE!)

### What are two characteristics of a credit union??

What are two characteristics of a credit union??...

### Solve for y. $\frac{2}{3}+y-\frac{1}{9}=\frac{7}{9} \\$ Enter your answer in the box. y =__

Solve for y. $\frac{2}{3}+y-\frac{1}{9}=\frac{7}{9} \\$ Enter your answer in the box. y =__...

### Which of the following enable a long-term resistance to infections that have been present in the body before? lymphocytes right?!

Which of the following enable a long-term resistance to infections that have been present in the body before? lymphocytes right?!...

### Leo the rabbit hops 1 or 2 stairs how many different ways can he climb 10 stairs

Leo the rabbit hops 1 or 2 stairs how many different ways can he climb 10 stairs...

### I need help with number 1 and 2 pls

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### What were the most important reasons why World War I began? Check all that apply. A. Nationalist movements were on the rise. B. Competition to colonize smaller countries rose. C. Countries were engaging in militarism. D. Countries were splitting into alliances. E. Countries were developing poison gas. Smaller countries rose up to fight imperialism.

What were the most important reasons why World War I began? Check all that apply. A. Nationalist movements were on the rise. B. Competition to colonize smaller countries rose. C. Countries were engaging in militarism. D. Countries were splitting into alliances. E. Countries were developing poison ga...

### Which describes a feature of synthetic polymers? They can be naturally decomposed. They can be cheaply recycled. They can only be made in small quantities. They can be produced at a low cost.

Which describes a feature of synthetic polymers? They can be naturally decomposed. They can be cheaply recycled. They can only be made in small quantities. They can be produced at a low cost....

### What was the effect of the end of wartime production at the conclusion of WWI?

what was the effect of the end of wartime production at the conclusion of WWI?...

### A club raises $3,207 to buy stuffed animals for a local children's hospital. Each stuffed animal costs$17. What is the maximum number of stuffed animals the club can buy?

A club raises $3,207 to buy stuffed animals for a local children's hospital. Each stuffed animal costs$17. What is the maximum number of stuffed animals the club can buy?...

### Solve the linear equation y=3x-2 y-2=x

solve the linear equation y=3x-2 y-2=x...

### How do I solve this?

How do I solve this?...

### Read the excerpt from Act II, scene vi of Romeo and Juliet. Friar Laurence: These violent delights have violent ends, And in their triumph die, like fire and powder, Which, as they kiss consume: the sweetest honey Is loathsome in his own deliciousness And in the taste confounds the appetite: Therefore love moderately; long love doth so; Too swift arrives as tardy as too slow. What mood is created by the oxymoron and paradox in this excerpt

Read the excerpt from Act II, scene vi of Romeo and Juliet. Friar Laurence: These violent delights have violent ends, And in their triumph die, like fire and powder, Which, as they kiss consume: the sweetest honey Is loathsome in his own deliciousness And in the taste confounds the appetite: Therefo...

### Not even gonna try answering this question cause it looks to complicated

not even gonna try answering this question cause it looks to complicated ...

### In an effort to help save an endangered Australian marsupial called the northern quoll, researchers paired a nausea-inducing drug with a toad the quolls often eat. In this application of a phenomenon called _____, the toads researchers used are a(n) _____.

In an effort to help save an endangered Australian marsupial called the northern quoll, researchers paired a nausea-inducing drug with a toad the quolls often eat. In this application of a phenomenon called _____, the toads researchers used are a(n) _____....

### Simplify. 5² KWHGFPB'pagr

Simplify. 5² KWHGFPB'pagr...

### Can someone teach me how to do a step by step explanation answer on brainly please

Can someone teach me how to do a step by step explanation answer on brainly please...

### X2+5x−9 complete the square of this equation

x2+5x−9 complete the square of this equation...


text:
A module for creating fractal art in Python's turtle module.

# fractalartmaker

A module for creating fractal art in Python's turtle module.

This module is explored in the book "The Recursive Book of Recursion" by Al Sweigart from No Starch Press.

You can purchase this book directly from the publisher at https://nostarch.com/recursive-book-recursion or read it online at https://inventwithpython.com/recursion/

# Quickstart

To view some example fractals, run the following from the interactive shell:

>>> import fractalartmaker
>>> fractalartmaker.fast()  # draw the fractals quickly
>>> fractalartmaker.example(1)  # pass 1 to 9

# Making Fractals

The Fractal Art Maker's algorithm has two major components: a shape-drawing function and the recursive drawFractal() function.

The shape-drawing function draws a basic shape. The Fractal Art Maker program comes with the two shape-drawing functions, fractalartmaker.drawFilledSquare() and fractalartmaker.drawTriangleOutline(), but you can also create your own. We pass a shape-drawing function to the fractalartmaker.drawFractal() function as an argument.

The fractalartmaker.drawFractal() function also has a parameter indicating changes to the size, position, and angle of the shapes between recursive calls to fractalartmaker.drawFractal().

The fractalartmaker.drawFractal() function uses a shape-drawing function passed to it to draw the individual parts of the fractal. This is usually a simple shape, such as a square or triangle. The beautiful complexity of the fractals emerges from fractalartmaker.drawFractal() recursively calling this function for each individual component of the whole fractal.

Here's the two shape-drawing functions that come in the fractalartmaker module:

def drawFilledSquare(size, depth):
size = int(size)

# Move to the top-right corner before drawing:
turtle.penup()
turtle.forward(size // 2)
turtle.left(90)
turtle.forward(size // 2)
turtle.left(180)
turtle.pendown()

# Alternate between white and gray (with black border):
if depth % 2 == 0:
turtle.pencolor('black')
turtle.fillcolor('white')
else:
turtle.pencolor('black')
turtle.fillcolor('gray')

# Draw a square:
turtle.begin_fill()
for i in range(4):  # Draw four lines.
turtle.forward(size)
turtle.right(90)
turtle.end_fill()

def drawTriangleOutline(size, depth):
size = int(size)

# Move the turtle to the top of the equilateral triangle:
height = size * math.sqrt(3) / 2
turtle.penup()
turtle.left(90)  # Turn to face upwards.
turtle.forward(height * (2/3))  # Move to the top corner.
turtle.right(150)  # Turn to face the bottom-right corner.
turtle.pendown()

# Draw the three sides of the triangle:
for i in range(3):
turtle.forward(size)
turtle.right(120)

The shape-drawing functions for the Fractal Art Maker have two parameters: size and depth. The size parameter is the length of the sides of the square or triangle it draws. The shape-drawing functions should always use arguments to turtle.forward() that are based on size so that the lengths will be proportionate to size at each level of recursion. Avoid code like turtle.forward(100) or turtle.forward(200); instead, use code that is based on the size parameter, like turtle.forward(size) or turtle.forward(size * 2). In Python's turtle module, turtle.forward(1) moves the turtle by one unit, which is not necessarily the same as one pixel.

The shape-drawing functions' second parameter is the recursive depth of fractalartmaker.drawFractal(). Your shape-drawing function can ignore this argument, but using it can cause interesting variations to the basic shape. For example, the fractalartmaker.drawFilledSquare() shape-drawing function uses depth to alternate between drawing white squares and gray squares. Keep this in mind if you'd like to create your own shape-drawing functions for the Fractal Art Maker program, as they must accept a size and depth argument.

The fractalartmaker.drawFractal() function has three required parameters and one optional one: shapeDrawFunction, size, specs, and optionally maxDepth. The shapeDrawFunction parameter expects a function, like fractalartmaker.drawFilledSquare or fractalartmaker.drawTriangleOutline. The size parameter expects the starting size passed to the drawing function. Often, a value between 100 and 500 is a good starting size, though this depends on the code in your shape-drawing function, and finding the right value may require experimentation.

The specs parameter expects a list of dictionaries that specify how the recursive shapes should change their size, position, and angle as drawFractal() recursively calls itself. These specifications are described later in this section. To prevent drawFractal() from recursing until it causes a stack overflow, the maxDepth parameter holds the number of times drawFractal() should recursively call itself. By default, maxDepth has a value of 8, but you can provide a different value if you want more recursive shapes or fewer.

The recursive calls to drawFractal() are based on the specification in the specs list’s dictionaries. For each dictionary, drawFractal() makes one recursive call to drawFractal(). If specs is a list with one dictionary, every call to drawFractal() results in only one recursive call to drawFractal(). If specs is a list with three dictionaries, every call to drawFractal() results in three recursive calls to drawFractal().

The dictionaries in the specs parameter provide specifications for each recursive call. Each of these dictionaries has the keys sizeChange, xChange, yChange, and angleChange. These dictate how the size of the fractal, the position of the turtle, and the heading of the turtle change for a recursive drawFractal() call.

• sizeChange (default is 1.0) - The next recursive shape’s size value is the current size multiplied by this value.
• xChange (default is 0.0) - The next recursive shape’s x-coordinate is the current x-coordinate plus the current size multiplied by this value.
• yChange (default is 0.0) - The next recursive shape’s y-coordinate is the current y-coordinate plus the current size multiplied by this value.
• angleChange (default is 0.0) - The next recursive shape’s starting angle is the current starting angle plus this value.

Let’s take a look at the specification dictionary for the Four Corners fractal, which is drawn when you call fractalartmaker.example(1). The call to drawFractal() for the Four Corners fractal passes the following list of dictionaries for the specs parameter:

fractalartmaker.drawFractal(fractalartmaker.drawFilledSquare, 350,
[{'sizeChange': 0.5, 'xChange': -0.5, 'yChange': 0.5},
{'sizeChange': 0.5, 'xChange': 0.5, 'yChange': 0.5},
{'sizeChange': 0.5, 'xChange': -0.5, 'yChange': -0.5},
{'sizeChange': 0.5, 'xChange': 0.5, 'yChange': -0.5}], 5)

The specs list has four dictionaries, so each call to drawFractal() that draws a square will, in turn, recursively call drawFractal() four more times to draw four more squares.

To determine the size of the next square to be drawn, the value for the sizeChange key is multiplied by the current size parameter. The first dictionary in the specs list has a sizeChange value of 0.5, which makes the next recursive call have a size argument of 350 * 0.5, or 175 units. This makes the next square half the size of the previous square. A sizeChange value of 2.0 would, for example, double the size of the next square. If the dictionary has no sizeChange key, the value defaults to 1.0 for no change to the size.

If you look at the three other dictionaries in the specs list, you’ll notice they all have a sizeChange value of 0.5. The difference between them is that their xChange and yChange values place them in the other three corners of the current square. As a result, the next four squares are drawn centered on the four corners of the current square.

The dictionaries in the specs list for this example don’t have an angleChange value, so this value defaults to 0.0 degrees. A positive angleChange value indicates a counterclockwise rotation, while a negative value indicates a clockwise rotation.

Take a look at the code in the module's example() function for more examples.

The fractalartmaker module also has a fractalartmaker.fast() function you can call to make the fractals draw quickly, and a fractalartmaker.clear() to clear the turtle drawing window.

## Project details

Uploaded source


text:
## LaTeX forum ⇒ Curricula Vitae / Résumés ⇒ Compilation:impossible Topic is solved

ModernCV, Friggeri, Plasmati, Classicthesis-CV, and more
templateuser
Posts: 679
Joined: Tue Mar 03, 2015 4:01 pm

### Compilation:impossible

Hi guys,
This template is really nice but since this morning there was no way to compile it.

I tried to fix some issues, according to what have been said in the topics before and in other forum across the internets..but without success.

Here are some issues encountered:

\RequirePackage[math-style=TeX,vargreek-shape=unicode]{unicode-math}^^MThe option quiet' was not declared in package fontspec', perhaps youmisspelled its name. Try typing <return> to proceed.  l.53 \newfontfamily\thinfont[]{Helvetica Neue CE 35 Thin}The control sequence at the end of the top lineof your error message was never \def'ed. If you havemisspelled it (e.g., \hobx'), type I' and the correctspelling (e.g., I\hbox'). Otherwise just continue,and I'll forget about whatever was undefined.! Undefined control sequence.[]\OT1/cmr/m/n/10 Mapping=tex-text [Mapping=tex-text, Color=textcolor]Helvetica Neue[]! Undefined control sequence.<argument> \fontspec_set_fontface:NNnn\l_um_font \l_um_family_tl {BoldItali...l.59 \setmathfont{XITS Math}The control sequence at the end of the top lineof your error message was never \def'ed. If you havemisspelled it (e.g., \hobx'), type I' and the correctspelling (e.g., I\hbox'). Otherwise just continue,and I'll forget about whatever was undefined.! Undefined control sequence.

And others...
I'm very new to LaTeX tough.
I compiled with xelatex and modified the font wich provoque some issues.

Hamza

Tags:

Stefan Kottwitz
Posts: 9567
Joined: Mon Mar 10, 2008 9:44 pm
Regarding this error:

The option quiet' was not declared in package fontspec', perhaps youmisspelled its name. Try typing <return> to proceed.

It seems the quiet option has been used but is not defined yet. From the manual:

fontspec manual wrote:This package can give many warnings that can be harmless if you know what you’re doing.
Use the [quiet] package option to write these warnings to the transcript (.log) file instead.
Use the [silent] package option to completely suppress these warnings if you don’t
even want the .log file cluttered up.

So in the current version it is defined. Possibly you simply need to update the fontspec package on your computer. For a consistent TeX setup, I recommend an update of the whole TeX installation.

The other errors could simply be a consequence or also be caused by using an older version. This can finally be said after seeing your code and your .log file.

Stefan

LucaCrippa
Posts: 1
Joined: Mon Aug 31, 2015 2:37 pm
Hi guys,

also for me compiling this template seems to be very hard. I'm using TeXworks (up-to-date), and as I choose XeLaTex I get this error:

! Undefined control sequence.<argument> \c_keys_code_root_tl                                  fontspec/Ligatures/Historicall.8 ...tureoption{Ligatures}{Historic}{Historical}

Thanks!

Johannes_B
Site Moderator
Posts: 4161
Joined: Thu Nov 01, 2012 4:08 pm
The smart way: Calm down and take a deep breath, read posts and provided links attentively, try to understand and ask if necessary.

Stefan Kottwitz
Posts: 9567
Joined: Mon Mar 10, 2008 9:44 pm
Hi Luca,

welcome to the forum!

I think the same. The message points to LaTeX3, which is developing, so there may be a gap somewhere - I would update my TeX too in that case.

Stefan


text:
# How do you find the axis of symmetry, and the maximum or minimum value of the function y=x^2+5x-7?

Nov 22, 2017

Axis of symmetry is $x = - 2.5$

and

${y}_{\min} = - 13.5$

#### Explanation:

This is the equation of a parabola in standard form, i.e.:

$y = a {x}^{2} + b x + c$

Here, $a = 1 , b = 5 , c = - 7$

This parabola opens up as we can see:

graph{x^2+5x-7 [-30.32, 30.32, -15.16, 15.16]}

The axis of symmetry is a vertical line and goes through the vertex. The $x$ coordinate of the vertex can be found from:

$x = - \frac{b}{2 a} = \frac{- 5}{2 \left(1\right)} = - 2.5$

Therefore the axis of symmetry is $x = - 2.5$

This function does not have a maximum as it goes to infinity on both sides. Its minimum is at its vertex. We can find it by finding the value of $y$ at the vertex. We do this by plugging the value of $x$ of the vertex into the equation:

${y}_{\min} = {\left(- 2.5\right)}^{2} + 5 \left(- 2.5\right) - 7 = 6.25 - 12.5 - 7 = - 13.5$


text:
#### Archived

This topic is now archived and is closed to further replies.

# exceptions

This topic is 5362 days old which is more than the 365 day threshold we allow for new replies. Please post a new topic.

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No one seems to answer, so I'll give it a shot...

What advantages does it have over, say a global variable indicating whether an error occured and what it was?

Simplicity. You don't have to check that global variable after every time you perform something and return some error value through a jungle of if (not error) 'do this' else 'do that' . You just do it (well, perhaps not just ). Also, some designs would not be possible without exceptions as a way of communicating an error; boost::lexical_cast would be an example. Let's say you are writing a templated container class, taking any type T. Inside the container, you make a copy of everything that is added to it. How should T tell the container and the user of the container that some error occured while copying? You could use some method is_ok() and return false, if T is a class, but that would rule out any primitive type and the container can only handle classes that implement is_ok(). It's not so generic any more. I don't know if my example was any good, but the point is that exceptions provide a standard way of handling errors. The container need only to provide some documented level of exception safety and leave the rest to the user.

Further, global variables has their own set of problems.

With both these approaches you can simply put all your code somewhere and check for errors when its convenient, and dont need to worry about ugly nested try{}catch{} statements

When it's convenient? Wouldn't it be convenient to handle errors when they occur? If it's ok for you to handle some errors when it's convenient, then don't use exceptions for those erros. Exceptions are best used for exceptional cases. This does not mean that it has to be some unrecoverable hardware error, when your home is about to explode, or etc, as I've gotten the impression that some might think. What's exceptional and what's not, depends on what you are doing. This does not mean that exceptions should replace simple return values.

Do you always have to catch all your exceptions if you dont want your program to crash?

Yes.

AFAIK, performance is only affected when setting up a try-catch block or when the exception is thrown.

What support does the OS need to supply for exception handling?

The OS has nothing to do with C++ exceptions. For Windows, there is also Structured Exception Handling, which is something different, but has a similar construct.

Edit: spelling

[edited by - Matsen on October 12, 2003 4:08:04 PM]

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quote:
Original post by aboeing
(I understand that you want to use it for detecting very low level errors, but most of the time these errors dont happen - Im talking about as a general error handling mechanism)

It *is* a better general purpose error handling mechanism.

Since it unwinds the stack EVERYTHING along the way can clean up or not handle the exception as it happens. Handlers can rethrow different exceptions or take actions like rollback a database to prevent destructive changes from happening.

A global variable holding the exception is okay, but then you have to make that local to the thread. Once you get around that, programs don''t have to check it, and it encourages a sort of irresponsible coding style where "this works most of the time." Then when something doesn''t work, go run post on Gamedev! If you don''t have an exception then your program stops RIGHT there and you can look at the exception and determine what happened if you provide enough information.

Also, using return values to indicate success/failure really isn''t necessary nowadays. Your ''nominal'' code path does not turn into a gigantic indentation because of all the if''s. The error handling logic is separate from the normal logic.

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quote:
Original post by Matsen
What support does the OS need to supply for exception handling?

The OS has nothing to do with C++ exceptions. For Windows, there is also Structured Exception Handling, which is something different, but has a similar construct.

On Windows, C++ exceptions are implemented on top of SEH.

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quote:
On Windows, C++ exceptions are implemented on top of SEH.
Yes, that''s true for a Microsoft compiler, but what about other compilers, such as gcc?

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The question basically is, why would you want to use C++ exception handling?

Because it is easier and safer than propagating errors by hand.
Exceptions propagate until they find the appropriate handler.

What advantages does it have over, say a global variable indicating whether an error occured and what it was?

Exceptions are always detected. Programers quite often forget to check error codes.

What advantages does it have over having a base class with an error variable, a pointer to its parent, and propogating the errors like that?

You can already arrange exceptions in a hierarchy and catch the base exceptions. I don''t quite understand the approach you are suggesting ? Is the base class an exceptiobn class ? Is it a base class of the objects you manipulate (setting the error member when an error occurs) ?

With both these approaches you can simply put all your code somewhere and check for errors when its convenient, and dont need to worry about ugly nested try{}catch{} statements.

Instead you will have to worry about whatever structure YOU put in place to emulate exceptions. Personally, I prefer using a construct that is directly supported by the language than a half-baked, untested alternative that may require me to actually do more work.

If you used the RAII idiom ( "Ressource Acquisition Is Initialisation" ) - Acquiring resources in constructors, releasing them in destructors, you don''t even have to worry about things like closing files, releasing locks, freeing memory blocks ...

Do you always have to catch all your exceptions if you dont want your program to crash?

Yes

(eg: loadtexture causes an exception, but its not critical, so I shouldn''t have to deal with it..)

If it is not an error, don''t throw an exception.

What are the performance issues related to exception handling?

None unless an exception is actually thrown, at which point you shouldn''t care for performance anyway - something wrong happened, you need to fix it before moving on. try is practically free, it is throw that is expensive.

Can exception handling be turned on/off for certain functions/classes?

Not in standard C++. Your compiler may let you do it as an extension.

What support does the OS need to supply for exception handling?

I don''t know.

(is it just a fancy term for an interrupt?)

No. Exceptions trigger a stack unwinding within your program until the appropriate handler is found (or the exception leaves main(), at which point terminate() is called). Interrupts suspend the execution of your program to execute a handler that ''lives'' outside of your program (possibly in kernel-land).

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Hi,
First of all, thank you everyone for your feedback!

Re:Matsen:
"Simplicity."
-> to me, exceptions seem less simple.
try {x;} catch() {}
is more code than:
x; if(error) {}

"If it's ok for you to handle some errors when it's convenient, then don't use exceptions for those errors"
This is what I figured, in which case I would need my own error handling system anyway, so why bother with exceptions?

"AFAIK, performance is only affected when setting up a try-catch block or when the exception is thrown."
Well, this is good, at least I dont have to be afraid of using them =)

Re:antareus:
"Also, using return values to indicate success/failure really isn't necessary nowadays. Your 'nominal' code path does not turn into a gigantic indentation because of all the if's. The error handling logic is separate from the normal logic. "
How do you seperate error handling from normal code with exceptions? Are you just saying that try{}catch{} is seperating it? It would seem nicer to have a seperate HandleError method for each class that would be automatically called if something went wrong.

Also, as I suggested, your error variable could maintain information as to where the error occured (__LINE__,__FILE__ etc) so I dont see the point of using exception handling for this reason.

Re:Fruny:
"Because it is easier and safer than propagating errors by hand."
Is this safer meaning that I'm likely to make a mistake in my error handling code, or do you mean something else?

"Exceptions are always detected. Programers quite often forget to check error codes."
This is also one of my major concerns about exceptions. Writing code like try{CreateDXEngine();}catch(){} try{CreateTexture();}catch(){} try{CreateMesh();}catch() try{Render();}catch() seems like a very ugly way for the end user to use a system.

"Ressource Acquisition Is Initialisation"
Agreed that exceptions would work quite nicely in this design, but I dont think its possible to develop my entire system this way.

"If it is not an error, don't throw an exception."
But what now? now I need some kind of not-exception error handling mechanism, and as I said before, doesnt this make exceptions redundant?

"Exceptions trigger a stack unwinding"
Sorry if I dont really understand, but does this mean extra information needs to be passed on the stack with every function call/whathaveyou?

-=-=-=--=-=-=--=-=-=--=-=-=--=-=-=--=-=-=--=-=-=--=-=-=--=-=-=-

From the overall response I can see that people like exceptions because they are language specific and they force users to deal with errors that happen. (personally, I'm not a fan of this, as users generally dont deal with errors, and I would prefer for my program to continue trying to run than have it exit and say "exception thrown blablabla")

The responses indicate that there are no performance reasons to not use exceptions, so I should use them.

Also, people say only to use exceptions for exceptional circumstances (makes sense.)
So this means you'll want some other method of error handling aswell. So, where do you draw the line? And what is the best method for doing so?

What I had in mind (Re:Fruny:"the approach you are suggesting?" ) was something like:
class Base {struct error_struct; //contain info such as __LINE__,etc.Base *parent; //point to my 'creator'void SetError(an_error_struct) {this->error_struct=an_error_structparent->notify_an_error_occured_and_call_set_error_if_appropriate}}class Texture{void Loadtexturefromfile(){if(filenotfound) SetError();}}class Model {void SetupModel() {Texture *mytex = Create("Texture",this); //automagically set parent//Load a bunch of texturesIf(erroroccured) {deal with it, if the texture wasnt critical to gameplay we can render the model anyway }}}

you get the general jist of it.. (you could easily extend this so that the base class had a HandleErrors() method that was automatically called as the error propogated..)

Thanks.

(edit:fixed italics)

[edited by - aboeing on October 13, 2003 8:57:03 AM]

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int* x1;int* x2;int* x3;int* x4;int* x5;try{  x1 = new int;  x2 = new int;  x3 = new int;  x4 = new int;  x5 = new int;}catch(...){ std::cout << "there was an error..." << std::endl;}If you would write the same code with if''s :int* x1 = new int;if(x1 == NULL) std::cout << "there was an error" << std::endl;int* x2 = new int;if(x2 == NULL) std::cout << "there was an error" << std::endl;int* x3 = new int;if(x3 == NULL) std::cout << "there was an error" << std::endl;int* x4 = new int;if(x4 == NULL) std::cout << "there was an error" << std::endl;int* x5 = new int;if(x5 == NULL) std::cout << "there was an error" << std::endl;

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quote:

deal with it, if the texture wasnt critical to gameplay we can render the model anyway

!!!LMAO!!!

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AP #1:
True, perhaps exception handling should be used for out-of-memory checks aswell, although in my experience I dont often need to do something like that. (most of the time my classes only have 1 or 2 non-class objects that need to be created).

Then again, do we consider out-of-memory an exceptional case?
I probably would. The other instances I would use it are for standard functions which could fail, or when you are calling a users-plugin which could have bad code in it. (naturally, all the code I would write would work perfectly, so this wouldn''t be necessary for me ) Any other opinions?
(eg:
FILE *fp;
try {
fp = fopen(filename, "a");
} catch (...) {
#ifdef WIN32
MessageBox(NULL,"Serious error has occured, could not call fopen!","Log::debug",MB_OK|MB_ICONWARNING);
#endif
return;
}
if (fp==NULL) return some_error;
)

AP #2:
Think of a quake3 map, and not all the textures are available for the map, the engine should still load and render what it can.

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text:
# Placing satellites

In a geostationary orbit around the earth satellites are to be placed at equal distances from each other in such a manner that each satellite can see every other during any instant of its motion.Find the maximum no of satellites that can be placed in such a manner.Assume that the space station cant send more than 10 satellites.Assume that the orbits are circular.

×


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# Which has greater momentum?

1. Nov 18, 2006

### blackout85

Two bodies of unequal mass, placed at rest on a frictionless surface, are acted on by an equal horizontal forces for equal times. Just after the forces are removed, the body of greater mass will have:
The body of greater mass will have the the greater speed, the greater acceleration, the smaller momentum, the greater momentum, or the same amount as the other body.

Would the answer be the larger body would have the same amount amount of momentum as the other body because P(before)=P(after). The momentum would have to come out the same in order for that to be right.

second question:

A 0.2kg rubber ball is dropped from the window of a building. It strikes the sidewalk below at 30m/s and rebounds up at 20m/s. The impulse during the collision would be:

my work:
0.2 (-30m/s) - 0.2 (20m/s) = 10 upward

Please let me know if I am on the right track and let me know where I might have gone wrong

2. Nov 18, 2006

Edit: the change in momentum (i.e. the impulse) should actually be: $$0.2\cdot 20\vec{j}-0.2\cdot(-30)\vec{j}=10\vec{j}$$, which means 10 upwards.


text:
# Unique Factorization Domains

Printable View

• Dec 17th 2009, 08:14 AM
pleasehelpme1
Unique Factorization Domains
Let p be a prime integer.

Prove that Z_p[x] is a unique factorization domain.

I need a legit proof to this if possible.
• Dec 17th 2009, 09:25 PM
NonCommAlg
Prove that Z_p is a unique factorization domain for prime p.
Quote:

Originally Posted by pleasehelpme1
Let p be a prime integer.

Prove that Z_p[x] is a unique factorization domain.

I need a legit proof to this if possible.

$\mathbb{Z}_p$ is a field and so $\mathbb{Z}_p[x]$ is a PID. now try to recall that every PID is a UFD.
• Dec 18th 2009, 06:24 AM
pleasehelpme1
???
why is this always the answer i get... you can just assume things like Z_p being a field. I don't see how that proves anything?
• Dec 18th 2009, 12:18 PM
tonio
Quote:

Originally Posted by pleasehelpme1
Prove that every irreducible is prime in Z_p where p is prime.

You are aware of the fact that $\mathbb{Z}_p$ is a FIELD for any prime $p$ ?? Because if you are then your question is trivial, and if you aren't then perhaps try to prove it: it isn't hard.

Tonio
• Dec 18th 2009, 01:29 PM
NonCommAlg
Quote:

Originally Posted by pleasehelpme1
Let p prime.

Prove that Z_p is a unique factorization domain.

a field is a PID and a PID is a UFD. (take a look at your lecture notes!)
• Dec 18th 2009, 02:51 PM
pleasehelpme1
....
i can't use that assumption. i have to prove it as if i don't know anything above.
• Dec 18th 2009, 04:52 PM
mr fantastic
This whole question is alewady under discussion here: http://www.mathhelpforum.com/math-he...need-help.html

Thread closed.


text:
Draw Primitive Can't Be This Slow

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Hi, im getting 41fps when rendering 2400 primitives in one batch out of 1 vertex buffer. The vertex buffer is being configured and filled in the app setup so not every frame. here is the frame render function:

void app_renderer::Render()
{
l_pD3DDevice->SetStreamSource( 0, vb, 0, sizeof(GENERICVERTEX3D) );
l_pD3DDevice->SetFVF( FVF_GENERICVERTEX3D );
SetTexture(3);
l_pD3DDevice->DrawPrimitive( D3DPT_TRIANGLELIST, 0, 2400 );
}

I have checked time and time again and the just contains 7200 vertices as a triangle list. Any ideas why its this slow. There is nothing else running per frame than standard graphics and when i stop it rendering these 2400 prims i get my usual 1300fps. regards, ace

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Are you rendering a lot of pixels? i.e. are you fillrate bound rather than vertex throughput limited?

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No, they barely fill the screen at all.

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Recently, i wasted many days to get max fps of rendering with vbs. So my experiences show that one DP or DIP call likes 1000 primitive. Or around 1000. And they like strip very much 20 - 30% performance gain. But it depends much of the sizes of a textures.

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The only other thing I can think is that you've switched on software vertex processing for a vertex buffer that's in AGP/video memory, thus requiring a slow readback.

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nope is on hardware

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... i don't suppose you've set debug output level to max?

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how do i do that?

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Quote:
 Original post by ace_lovegrovehow do i do that?

http://www.gamedev.net/community/forums/showfaq.asp?forum_id=10#controlpanel

http://www.gamedev.net/community/forums/showfaq.asp?forum_id=10#debugging

If D3D is unhappy about something and you're using the debug runtimes (you should be for development), then you'll be getting a lot of errors sent to your debug output stream - a few errors each frame and your frame rate will quickly plummet.

Of course there could be other problems too such as how/when you're locking the vertex buffer and which memory pool you've specified for the vertex buffer - if you give us some more details of what your application is doing, we'll be able to help more.

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