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diff --git a/src/statisticsFunctions/variance/zvariancea.c b/src/statisticsFunctions/variance/zvariancea.c
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+++ b/src/statisticsFunctions/variance/zvariancea.c
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+/*
+ *  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"
+
+doubleComplex	zvariancea(doubleComplex *in, int size)
+{
+    int i = 0 ;
+    
+    /*here sumcis used to compensate the possible round off error to a less
+     important degree */
+    
+    doubleComplex sum  = DoubleComplex ( 0 , 0 ) ;
+    doubleComplex temp = DoubleComplex ( 0 , 0 ) ; 
+    doubleComplex sumc = DoubleComplex ( 0 , 0 ) ;
+    doubleComplex variance = DoubleComplex ( 0 , 0 );
+    doubleComplex mean =  zmeana ( in , size ) ;
+     
+    for ( i = 0 ; i < size ; i++)
+    {
+
+       temp = zdiffs( in[i] , mean ) ;
+       sum  = zadds ( sum , zpows ( temp  , DoubleComplex ( 2, 0) ) );
+       sumc = zadds ( sumc , temp ); 
+        printf ( "%d r : %e  i : %e\n" , i , zreals(in[i]) , zimags (in[i])); 
+    }
+    printf ( "\n\n" ) ;
+   /*we don't use sumc if equal to 0 otherwise we would have "nan" */
+   if ( fabs ( zreals ( sumc)) > 1e-16 || fabs ( zimags ( sumc)) > 1e-16 )
+    {
+    variance = zpows ( sumc ,DoubleComplex (2 , 0)) ;     
+    variance = zdevides ( variance  , DoubleComplex ( size , 0 ) ) ;           
+    variance =  zdiffs ( sum , variance );      
+    variance = zdevides (variance , DoubleComplex ( (size - 1),0 )); 
+    }
+   else 
+          variance = zdevides (sum , DoubleComplex ( (size - 1),0 ));
+  
+    return variance ;
+}
+