[Overview][Constants][Types][Classes][Procedures and functions][Index] |
Return mean and standard deviation of array
Source position: math.pp line 521
procedure MeanAndStdDev( |
const data: array of Single; |
var mean: Float; |
var stddev: Float |
); |
const data: PSingle; |
const N: LongInt; |
var mean: Float; |
var stddev: Float |
); |
const data: array of Double; |
var mean: Float; |
var stddev: Float |
); |
const data: PDouble; |
const N: LongInt; |
var mean: Float; |
var stddev: Float |
); |
const data: array of Extended; |
var mean: Float; |
var stddev: Float |
); |
const data: PExtended; |
const N: LongInt; |
var mean: Float; |
var stddev: Float |
); |
meanandstddev calculates the mean and standard deviation of data and returns the result in mean and stddev, respectively. Stddev is zero if there is only one value. The second form accepts a pointer to an array of N values.
None.
|
Return mean value of array |
|
|
Return sum of values |
|
|
Return sum of squares of values |
|
|
Return 4 first moments of distribution |
Program Example28; { Program to demonstrate the Meanandstddev function. } { @ should return typed pointer } {$T+} Uses math; Type TExArray = Array[1..100] of Extended; Var I : Integer; ExArray : TExArray; Mean,stddev : Extended; begin Randomize; for I:=low(ExArray) to high(ExArray) do ExArray[i]:=(Random-Random)*100; MeanAndStdDev(ExArray,Mean,StdDev); Writeln('Mean : ',Mean:8:4); Writeln('StdDev : ',StdDev:8:4); MeanAndStdDev(@ExArray[1],100,Mean,StdDev); Writeln('Mean (b) : ',Mean:8:4); Writeln('StdDev (b) : ',StdDev:8:4); end.