Remove example and experimental
@@ -44,37 +44,7 @@ the result.
The following trigonometric binary operators, which work in radians, exist in Prometheus:
-* `atan2` (based on https://pkg.go.dev/math#Atan2, _This is experimental_)
-
- A usecase of `atan2` is converting directional data between the [polar](https://en.wikipedia.org/wiki/Polar_coordinate_system) (r, theta)
- and [cartesian](https://en.wikipedia.org/wiki/Cartesian_coordinate_system) (x, y) coordinate forms.
-
- Example:
-
- Take some wind speed and direction data in the polar form. To get a trend over a
- longer period of time, it's not correct to just average out the direction data.
- The polar data needs to be converted into the cartesian form:
-
- ```
- wind:northwards = windspeed * cos(rad(winddirection))
- wind:westwards = windspeed * sin(rad(winddirection))
- ```
-
- Having done that, the longerterm averages over northwards and westwards now make sense:
-
- ```
- wind:northwards:avg1h = avg_over_time(wind:northwards[1h])
- wind:westwards:avg1h = avg_over_time(wind:westwards[1h])
- ```
-
- The "average" direction can be extracted out of these again by using `atan2`:
-
- ```
- wind:direction:avg1h = deg(wind:northwards:avg1h atan2 wind:westwards:avg1h)
- ```
-
- The Wikipedia article on the circular mean has more about this calculation:
- https://en.wikipedia.org/wiki/Circular_mean
+* `atan2` (based on https://pkg.go.dev/math#Atan2)
Trigonometric operators allow trigonometric functions to be executed on two vectors using
vector matching, which isn't available with normal functions. They act in the same manner
