diff maths/MathUtilities.cpp @ 241:a98dd8ec96f8

* Move dsp/maths to maths ; bring PCA and HMM across from Soundbite

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/maths/MathUtilities.cpp	Wed Jan 09 10:31:29 2008 +0000
@@ -0,0 +1,221 @@
+/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
+
+/*
+    QM DSP Library
+
+    Centre for Digital Music, Queen Mary, University of London.
+    This file copyright 2005-2006 Christian Landone.
+    All rights reserved.
+*/
+
+#include "MathUtilities.h"
+
+#include <iostream>
+#include <cmath>
+
+
+double MathUtilities::mod(double x, double y)
+{
+    double a = floor( x / y );
+
+    double b = x - ( y * a );
+    return b;
+}
+
+double MathUtilities::princarg(double ang)
+{
+    double ValOut;
+
+    ValOut = mod( ang + M_PI, -2 * M_PI ) + M_PI;
+
+    return ValOut;
+}
+
+void MathUtilities::getAlphaNorm(const double *data, unsigned int len, unsigned int alpha, double* ANorm)
+{
+    unsigned int i;
+    double temp = 0.0;
+    double a=0.0;
+	
+    for( i = 0; i < len; i++)
+    {
+	temp = data[ i ];
+		
+	a  += ::pow( fabs(temp), alpha );
+    }
+    a /= ( double )len;
+    a = ::pow( a, ( 1.0 / (double) alpha ) );
+
+    *ANorm = a;
+}
+
+double MathUtilities::getAlphaNorm( const std::vector <double> &data, unsigned int alpha )
+{
+    unsigned int i;
+    unsigned int len = data.size();
+    double temp = 0.0;
+    double a=0.0;
+	
+    for( i = 0; i < len; i++)
+    {
+	temp = data[ i ];
+		
+	a  += ::pow( fabs(temp), alpha );
+    }
+    a /= ( double )len;
+    a = ::pow( a, ( 1.0 / (double) alpha ) );
+
+    return a;
+}
+
+double MathUtilities::round(double x)
+{
+    double val = (double)floor(x + 0.5);
+  
+    return val;
+}
+
+double MathUtilities::median(const double *src, unsigned int len)
+{
+    unsigned int i, j;
+    double tmp = 0.0;
+    double tempMedian;
+    double medianVal;
+ 
+    double* scratch = new double[ len ];//Vector < double > sortedX = Vector < double > ( size );
+
+    for ( i = 0; i < len; i++ )
+    {
+	scratch[i] = src[i];
+    }
+
+    for ( i = 0; i < len - 1; i++ )
+    {
+	for ( j = 0; j < len - 1 - i; j++ )
+	{
+	    if ( scratch[j + 1] < scratch[j] )
+	    {
+		// compare the two neighbors
+		tmp = scratch[j]; // swap a[j] and a[j+1]
+		scratch[j] = scratch[j + 1];
+		scratch[j + 1] = tmp;
+	    }
+	}
+    }
+    int middle;
+    if ( len % 2 == 0 )
+    {
+	middle = len / 2;
+	tempMedian = ( scratch[middle] + scratch[middle - 1] ) / 2;
+    }
+    else
+    {
+	middle = ( int )floor( len / 2.0 );
+	tempMedian = scratch[middle];
+    }
+
+    medianVal = tempMedian;
+
+    delete [] scratch;
+    return medianVal;
+}
+
+double MathUtilities::sum(const double *src, unsigned int len)
+{
+    unsigned int i ;
+    double retVal =0.0;
+
+    for(  i = 0; i < len; i++)
+    {
+	retVal += src[ i ];
+    }
+
+    return retVal;
+}
+
+double MathUtilities::mean(const double *src, unsigned int len)
+{
+    double retVal =0.0;
+
+    double s = sum( src, len );
+	
+    retVal =  s  / (double)len;
+
+    return retVal;
+}
+
+void MathUtilities::getFrameMinMax(const double *data, unsigned int len, double *min, double *max)
+{
+    unsigned int i;
+    double temp = 0.0;
+    double a=0.0;
+	
+    *min = data[0];
+    *max = data[0];
+
+    for( i = 0; i < len; i++)
+    {
+	temp = data[ i ];
+
+	if( temp < *min )
+	{
+	    *min =  temp ;
+	}
+	if( temp > *max )
+	{
+	    *max =  temp ;
+	}
+		
+    }
+}
+
+int MathUtilities::getMax( double* pData, unsigned int Length, double* pMax )
+{
+	unsigned int index = 0;
+	unsigned int i;
+	double temp = 0.0;
+	
+	double max = pData[0];
+
+	for( i = 0; i < Length; i++)
+	{
+		temp = pData[ i ];
+
+		if( temp > max )
+		{
+			max =  temp ;
+			index = i;
+		}
+		
+   	}
+
+	*pMax = max;
+
+
+	return index;
+}
+
+void MathUtilities::circShift( double* pData, int length, int shift)
+{
+	shift = shift % length;
+	double temp;
+	int i,n;
+
+	for( i = 0; i < shift; i++)
+	{
+		temp=*(pData + length - 1);
+
+		for( n = length-2; n >= 0; n--)
+		{
+			*(pData+n+1)=*(pData+n);
+		}
+
+        *pData = temp;
+    }
+}
+
+int MathUtilities::compareInt (const void * a, const void * b)
+{
+  return ( *(int*)a - *(int*)b );
+}
+