2.1.24.4.28 ocmath_f_mean_variance

1 Description
2 Syntax
3 Parameters
4 Return
5 Examples
6 Remark
7 See Also
8 Header to Include
9 Reference

Description

calculate mean and variance, and also supports missing value.

Syntax

double ocmath_f_mean_variance( const float * pData, UINT nSize, double * prVariance, UINT * pnActualSampleSize = NULL, const float * pNAN = NULL )

Parameters

pData: [input] buffer containing data
nSize: [input] size of pData
prVariance: [output] return Variance of pData.
pnActualSampleSize: [output] actual sample size(actual data number in pData)
pNAN: [input] missing value

Return

mean

Examples

EX1

void ocmath_f_mean_variance_ex1()
{
    Worksheet wks = Project.ActiveLayer();
    wks.SetSize(-1,2);
    DataRange dr;
    dr.Add("X", wks, 0, 0, -1, 0);
    dr.Add("Y", wks, 0, 1, -1, 1);
    
    vector vxData, vyData;
    DWORD dwPlotID;
    if(dr.GetData(DRR_GET_MISSING | DRR_GET_DEPENDENT | DRR_NO_FACTORS, 0, &dwPlotID, NULL, &vyData, &vxData) < 0)
    {
            printf("get data failed!");
            return;
    }
    
    uint     nSize = vyData.GetSize();
    double     dVariance;
    uint     nActualSampleSize;
    double     dMean = ocmath_d_mean_variance(vyData, nSize, &dVariance, &nActualSampleSize);
}