1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
|
/*
* Scilab ( http://www.scilab.org/ ) - This file is part of Scilab
* Copyright (C) 2008-2008 - INRIA - Allan SIMON
*
* This file must be used under the terms of the CeCILL.
* This source file is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
* are also available at
* http://www.cecill.info/licences/Licence_CeCILL_V2-en.txt
*
*/
#include "variance.h"
floatComplex cvariancea(floatComplex *in, int size)
{
int i = 0 ;
/*here sumcis used to compensate the possible round off error to a less
important degree */
floatComplex sum = FloatComplex ( 0 , 0 ) ;
floatComplex temp = FloatComplex ( 0 , 0 ) ;
floatComplex sumc = FloatComplex ( 0 , 0 ) ;
floatComplex variance = FloatComplex ( 0 , 0 );
floatComplex mean = cmeana ( in , size ) ;
for ( i = 0 ; i < size ; i++)
{
temp = cdiffs( in[i] , mean ) ;
sum = cadds ( sum , cpows ( temp , FloatComplex ( 2.0f, 0) ) );
sumc = cadds ( sumc , temp );
printf ( "%d r : %e i : %e\n" , i , creals(in[i]) , cimags (in[i]));
}
printf ( "\n\n" ) ;
/*we don't use sumc if equal to 0 otherwise we would have "nan" */
if ( fabs ( creals ( sumc)) > 1e-08 || fabs ( cimags ( sumc)) > 1e-08 )
{
variance = cpows ( sumc ,FloatComplex (2.0f , 0)) ;
variance = cdivides ( variance , FloatComplex ((float) size , 0 ) ) ;
variance = cdiffs ( sum , variance );
variance = cdivides (variance , FloatComplex ((float) (size - 1),0 ));
}
else
variance = cdivides (sum , FloatComplex ((float) (size - 1),0 ));
return variance ;
}
|
