[Overview][Constants][Types][Classes][Procedures and functions][Index] Reference for unit 'Math' (#rtl)

PopnVariance

Return population variance

Declaration

Source position: math.pp line 525

function PopnVariance(

  const data: PSingle;

  const N: Integer

):Float;

function PopnVariance(

  const data: array of Single

):Float;

function PopnVariance(

  const data: PDouble;

  const N: Integer

):Float;

function PopnVariance(

  const data: array of Double

):Float;

function PopnVariance(

  const data: PExtended;

  const N: Integer

):Float;

function PopnVariance(

  const data: array of Extended

):Float;

Description

Popnvariance the population variance of the values in the Data array. It returns zero if there is only one value.

The second form of this function accepts a pointer to an array of N values.

Errors

None.

See also

popnstddev

  

Return Population standard deviation

mean

  

Return mean value of array

meanandstddev

  

Return mean and standard deviation of array

stddev

  

Return standard deviation of data

momentskewkurtosis

  

Return 4 first moments of distribution

Example

Program Example36;

{ Program to demonstrate the PopnVariance function. }
{ @ should return typed pointer }
{$T+}

Uses math;

Var
  I : Integer;
  ExArray : Array[1..100] of Float;

begin
  Randomize;
  for I:=low(ExArray) to high(ExArray) do
    ExArray[i]:=(Random-Random)*100;
  Writeln('Max           : ',MaxValue(ExArray):8:4);
  Writeln('Min           : ',MinValue(ExArray):8:4);
  Writeln('Pop. var.     : ',PopnVariance(ExArray):8:4);
  Writeln('Pop. var. (b) : ',PopnVariance(@ExArray[1],100):8:4);
end.

Documentation generated on: Jun 23 2021