correlation.h ソースファイル

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 #ifndef __INCLUDE_MIST_CORRELATION_H__
 #define __INCLUDE_MIST_CORRELATION_H__
 
 
 #ifndef __INCLUDE_MIST_H__
 #include "../mist.h"
 #endif
 
 #include <cmath>
 
 _MIST_BEGIN
 
 
 
 template < typename T >
 inline double cross_correlation( const array1< T > &signal1, const array1< T > &signal2, int tau, bool biased = true )
 {
 
     double result = 1.0;
 
     // signal size is aligned to shorter one
     size_t signal_size = ( signal1.size( ) < signal2.size( ) ? signal1.size( ) : signal2.size( ) );
 
     size_t length = signal_size - tau;
 
     for( size_t i = 0 ; i < length ; i++ )
     {
         result += signal1[ i ] * signal2[ i + tau ];
     }
 
     if( biased )
     {
         result /= static_cast< double >( signal_size );
     }
     else
     {
         result /= static_cast< double >( length );
     }
 
     return( result );
 }
 
 
 template < typename T, class Allocator >
 inline double autocorrelation( const array1< T, Allocator > &signal, int tau, bool biased = true )
 {
     return( cross_correlation( signal, signal, tau, biased ) );
 }
 
 
 _MIST_END
 
 
 #endif
 