Stat Assembly > Stat Assembly Interfaces > IStatistics > IStatistics.StDev

IStatistics.StDev

Syntax

StDev(Values: Array): Double;

Parameters

Values. Array of the data that corresponds to the sample of general population.

NOTE. If the data corresponds to the entire general population, the standard deviation should be estimated using the StDevP function.

Description

The StDev method estimates standard deviation by a sample.

Comments

The standard deviation is a measure showing how widely data points are spread relative to the mean. The standard deviation is calculated using unbiased or n-1 method.

Example

To execute the example, add a link to the Stat system assembly.

Sub UserProc;
Var
    st: Statistics;
    d0: Double;
    y: Array Of Double;
Begin
    y := New Double[10];
    y[00] := 6;
    y[01] := 17;
    y[02] := 9;
    y[03] := 15;
    y[04] := 21;
    y[05] := 24;
    y[06] := 20;
    y[07] := 21;
    y[08] := 14;
    y[09] := 25;
    st := New Statistics.Create;
    d0 := st.StDev(y);
    Debug.WriteLine("Standard deviation: " + d0.ToString);
End Sub UserProc;

Executing the example shows the standard deviation value in the console window:

Unit execution started

Standard deviation: 6.25033332444492

Unit execution finished