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Return standard deviation of data
Source position: math.pp line 470
| function stddev( | 
| const data: array of Single | 
| ):Float; | 
| const data: PSingle; | 
| const N: Integer | 
| ):Float; | 
| const data: array of Double | 
| ):Float; | 
| const data: PDouble; | 
| const N: Integer | 
| ):Float; | 
| const data: array of Extended | 
| ):Float; | 
| const data: PExtended; | 
| const N: Integer | 
| ):Float; | 
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.
None.
| 
 | Return mean value of array | |
| 
 | Return mean and standard deviation of array | |
| 
 | Return variance of values | |
| 
 | Return total varians of values | 
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.