popnvariance

Return population variance

Declaration

Source position: math.pp line 485

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.

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.

popnstddev		Return population variance
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

popnvariance

Declaration

Description

Errors

See also

Example