view maths/MathUtilities.cpp @ 209:ccd2019190bf msvc

Some MSVC fixes, including (temporarily, probably) renaming the FFT source file to avoid getting it mixed up with the Vamp SDK one in our object dir
author Chris Cannam
date Thu, 01 Feb 2018 16:34:08 +0000
parents 26daede606a8
children
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/* -*- 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 2005-2006 Christian Landone.

    This program is free software; you can redistribute it and/or
    modify it under the terms of the GNU General Public License as
    published by the Free Software Foundation; either version 2 of the
    License, or (at your option) any later version.  See the file
    COPYING included with this distribution for more information.
*/

#include "MathUtilities.h"

#include <iostream>
#include <algorithm>
#include <vector>
#include <cmath>

using namespace std;

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, int len, int alpha, double* ANorm)
{
    int i;
    double temp = 0.0;
    double a=0.0;
	
    for( i = 0; i < len; i++)
    {
	temp = data[ i ];
		
	a  += ::pow( fabs(temp), double(alpha) );
    }
    a /= ( double )len;
    a = ::pow( a, ( 1.0 / (double) alpha ) );

    *ANorm = a;
}

double MathUtilities::getAlphaNorm( const vector <double> &data, int alpha )
{
    int i;
    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), double(alpha) );
    }
    a /= ( double )len;
    a = ::pow( a, ( 1.0 / (double) alpha ) );

    return a;
}

double MathUtilities::round(double x)
{
    if (x < 0) {
        return -floor(-x + 0.5);
    } else {
        return floor(x + 0.5);
    }
}

double MathUtilities::median(const double *src, int len)
{
    if (len == 0) return 0;
    
    vector<double> scratch;
    for (int i = 0; i < len; ++i) scratch.push_back(src[i]);
    sort(scratch.begin(), scratch.end());

    int middle = len/2;
    if (len % 2 == 0) {
        return (scratch[middle] + scratch[middle - 1]) / 2;
    } else {
        return scratch[middle];
    }
}

double MathUtilities::sum(const double *src, int len)
{
    int i ;
    double retVal =0.0;

    for(  i = 0; i < len; i++)
    {
	retVal += src[ i ];
    }

    return retVal;
}

double MathUtilities::mean(const double *src, int len)
{
    double retVal =0.0;

    if (len == 0) return 0;

    double s = sum( src, len );
	
    retVal =  s  / (double)len;

    return retVal;
}

double MathUtilities::mean(const vector<double> &src,
                           int start,
                           int count)
{
    double sum = 0.;
	
    if (count == 0) return 0;
    
    for (int i = 0; i < (int)count; ++i)
    {
        sum += src[start + i];
    }

    return sum / count;
}

void MathUtilities::getFrameMinMax(const double *data, int len, double *min, double *max)
{
    int i;
    double temp = 0.0;

    if (len == 0) {
        *min = *max = 0;
        return;
    }
	
    *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, int Length, double* pMax )
{
	int index = 0;
	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;
		}
		
   	}

	if (pMax) *pMax = max;


	return index;
}

int MathUtilities::getMax( const vector<double> & data, double* pMax )
{
	int index = 0;
	int i;
	double temp = 0.0;
	
	double max = data[0];

	for( i = 0; i < int(data.size()); i++)
	{
		temp = data[ i ];

		if( temp > max )
		{
			max =  temp ;
			index = i;
		}
		
   	}

	if (pMax) *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 );
}

void MathUtilities::normalise(double *data, int length, NormaliseType type)
{
    switch (type) {

    case NormaliseNone: return;

    case NormaliseUnitSum:
    {
        double sum = 0.0;
        for (int i = 0; i < length; ++i) {
            sum += data[i];
        }
        if (sum != 0.0) {
            for (int i = 0; i < length; ++i) {
                data[i] /= sum;
            }
        }
    }
    break;

    case NormaliseUnitMax:
    {
        double max = 0.0;
        for (int i = 0; i < length; ++i) {
            if (fabs(data[i]) > max) {
                max = fabs(data[i]);
            }
        }
        if (max != 0.0) {
            for (int i = 0; i < length; ++i) {
                data[i] /= max;
            }
        }
    }
    break;

    }
}

void MathUtilities::normalise(vector<double> &data, NormaliseType type)
{
    switch (type) {

    case NormaliseNone: return;

    case NormaliseUnitSum:
    {
        double sum = 0.0;
        for (int i = 0; i < (int)data.size(); ++i) sum += data[i];
        if (sum != 0.0) {
            for (int i = 0; i < (int)data.size(); ++i) data[i] /= sum;
        }
    }
    break;

    case NormaliseUnitMax:
    {
        double max = 0.0;
        for (int i = 0; i < (int)data.size(); ++i) {
            if (fabs(data[i]) > max) max = fabs(data[i]);
        }
        if (max != 0.0) {
            for (int i = 0; i < (int)data.size(); ++i) data[i] /= max;
        }
    }
    break;

    }
}

double MathUtilities::getLpNorm(const vector<double> &data, int p)
{
    double tot = 0.0;
    for (int i = 0; i < int(data.size()); ++i) {
        tot += abs(pow(data[i], p));
    }
    return pow(tot, 1.0 / p);
}

vector<double> MathUtilities::normaliseLp(const vector<double> &data,
                                               int p,
                                               double threshold)
{
    int n = int(data.size());
    if (n == 0 || p == 0) return data;
    double norm = getLpNorm(data, p);
    if (norm < threshold) {
        return vector<double>(n, 1.0 / pow(n, 1.0 / p)); // unit vector
    }
    vector<double> out(n);
    for (int i = 0; i < n; ++i) {
        out[i] = data[i] / norm;
    }
    return out;
}
    
void MathUtilities::adaptiveThreshold(vector<double> &data)
{
    int sz = int(data.size());
    if (sz == 0) return;

    vector<double> smoothed(sz);
	
    int p_pre = 8;
    int p_post = 7;

    for (int i = 0; i < sz; ++i) {

        int first = max(0,      i - p_pre);
        int last  = min(sz - 1, i + p_post);

        smoothed[i] = mean(data, first, last - first + 1);
    }

    for (int i = 0; i < sz; i++) {
        data[i] -= smoothed[i];
        if (data[i] < 0.0) data[i] = 0.0;
    }
}

bool
MathUtilities::isPowerOfTwo(int x)
{
    if (x < 1) return false;
    if (x & (x-1)) return false;
    return true;
}

int
MathUtilities::nextPowerOfTwo(int x)
{
    if (isPowerOfTwo(x)) return x;
    if (x < 1) return 1;
    int n = 1;
    while (x) { x >>= 1; n <<= 1; }
    return n;
}

int
MathUtilities::previousPowerOfTwo(int x)
{
    if (isPowerOfTwo(x)) return x;
    if (x < 1) return 1;
    int n = 1;
    x >>= 1;
    while (x) { x >>= 1; n <<= 1; }
    return n;
}

int
MathUtilities::nearestPowerOfTwo(int x)
{
    if (isPowerOfTwo(x)) return x;
    int n0 = previousPowerOfTwo(x), n1 = nextPowerOfTwo(x);
    if (x - n0 < n1 - x) return n0;
    else return n1;
}

double
MathUtilities::factorial(int x)
{
    if (x < 0) return 0;
    double f = 1;
    for (int i = 1; i <= x; ++i) {
	f = f * i;
    }
    return f;
}

int
MathUtilities::gcd(int a, int b)
{
    int c = a % b;
    if (c == 0) {
        return b;
    } else {
        return gcd(b, c);
    }
}