# CFLib.org – Common Function Library Project

## StdDevPop(values)

##### Last updated September 07, 2001

Version: 1 | Requires: CF5 | Library: MathLib

Description:
Returns the standard deviation calculated using the divisor n method. This method is used when you have all the values for an entire population.

Return Values:
Returns a simple value.

Example:

``````<CFSET Values="1,2,3,4,5,6,7,8,9,10">

<CFOUTPUT>
Given <CFIF IsArray(Values)>{#ArrayToList(Values)#}<CFELSE>{#Values#}</CFIF><BR>
The standard deviation for the population is #StdDevPop(values)#
</CFOUTPUT>
``````

Parameters:

Name Description Required
values Comma delimited list or one dimensional array of numeric values. Yes

Full UDF Source:

``````/**
* Returns the standard deviation calculated using the divisor n method.
*
* @param values      Comma delimited list or one dimensional array of numeric values.
* @return Returns a simple value.
* @author Rob Brooks-Bilson (rbils@amkor.com)
* @version 1.1, September 7, 2001
*/
function StdDevPop(values)
{
Var MyArray = 0;
Var NumValues = 0;
Var xBar = 0;
Var SumxBar = 0;
Var i=0;
if (IsArray(values)){
MyArray = values;
}
else {
MyArray = ListToArray(values);
}
NumValues = ArrayLen(MyArray);
xBar = ArrayAvg(MyArray);
for (i=1; i LTE NumValues; i=i+1) {
SumxBar = SumxBar + ((MyArray[i] - xBar)*(MyArray[i] - xBar));
}
Return Sqr(SumxBar/NumValues);
}
``````

### Latest Additions

Raymond Camden added
QueryDeleteRows
November 04, 2017

Leigh added
nullPad
May 11, 2016

Raymond Camden added
stripHTML
May 10, 2016

Kevin Cotton added
date2ExcelDate
May 05, 2016

Raymond Camden added
CapFirst
April 25, 2016

Created by Raymond Camden / Design by Justin Johnson