code: def scalar(self, value, step, name):
          
          # Spaces not allowed for scalar variable name
          assert len(name.split(" ")) < 2, "Ensure that you don't have spaces in your variable name, use '_' instead."
          name = "scalar_" + name
          self.previous.append(name)
          if self.previous[-1] not in self.previous[:-1]:
              self.c.execute("""INSERT INTO {time_stamp_table} (
                                variable_name, variable_type
                                ) VALUES ('{variable}', '{type}')"""
                             .format(time_stamp_table=self.time_stamp, variable=name, type="scalar"))
          else:
              self.previous.pop()
  
          self.c.execute("""CREATE TABLE IF NOT EXISTS {variable_table_name} (
                            X_value FLOAT, Y_value FLOAT, time VARCHAR
                            )""".format(variable_table_name=self.time_stamp + '_' + name))
  
          self.c.execute("""INSERT INTO {variable_table_name} (
                            X_value, Y_value, time) VALUES ('{x}', '{y}', '{time}'
                            )""".format(variable_table_name=self.time_stamp + '_' + name,
                                        x=step, y=value, time=datetime.datetime.now()))
          self.conn.commit()
docs: Plot a scalar value.
          :param value: int or float, the value on the y-axis
          :param step: int or float, the value on the x-axis
          :param name: String, the name of the variable to be used during visualization