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StdDev function

In unit Math

Return standard deviation of data.

Declaration

pascal
function StdDev(const data: Array of Single): Float

Description

Stddev returns the standard deviation of the values in Data. It returns zero if there is only one value.

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

Errors

None.

See also

Example: ex43

pascal
Program Example40;

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

Uses Math;

Var
  I : Integer;
  ExArray : Array[1..10000] of Float;

begin
  Randomize;
  for I:=low(ExArray) to high(ExArray) do
    ExArray[i]:=Randg(1,0.2);
  Writeln('StdDev     : ',StdDev(ExArray):8:4);
  Writeln('StdDev (b) : ',StdDev(@ExArray[1],10000):8:4);
end.

An experiment, built from development snapshots. Not the official Free Pascal or Lazarus documentation.