utilities.cpp

此代码经过大量使用

/***************************************************************************
                          utilities.cpp  -  description
                             -------------------
    begin                : Wed May 22 2002
    copyright            : (C) 2002 by R黡iger Koch
    email                : [e-mail]
 ***************************************************************************/

/***************************************************************************
 *                                                                         *
 *   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.                                   *
 *                                                                         *
 ***************************************************************************/

using namespace std;
#include <amygdala/utilities.h>

#include <math.h>
#include <stdlib.h>
#include <stdio.h>
#include <string>
#include <stdexcept>
#include <sys/types.h>
#include <sys/stat.h>

float Utilities::GaussRand(float mean, float sigma)
{
    // Based on code from the GNU Scientific Library
    // and _Numerical Recipes in C_
	float randVal, xuniRand, yuniRand;
    float x, y, r2;

  	do {
      	// choose x,y in uniform square (-1,-1) to (+1,+1)
		xuniRand = float(rand()) / float(RAND_MAX);
		yuniRand = float(rand()) / float(RAND_MAX);

		x = -1 + 2 * xuniRand;
      	y = -1 + 2 * yuniRand;

      	// see if it is in the unit circle
       	r2 = x * x + y * y;
    } while (r2 > 1.0 || r2 == 0);

  	// Box-Muller transform
  	randVal = sigma * y * sqrt(-2.0 * log(r2) / r2);
	return (randVal + mean);
}

float Utilities::RandPercent()
{
    return ( float(rand()) / float(RAND_MAX) ) * 100.0;
}


string Utilities::itostr(int val){
    string retStr;
    char buf[255];
    sprintf(buf, "%i", val);
    retStr = buf;
    return retStr;
}


string Utilities::ftostr(float val){
    string retStr;
    char buf[255];

    sprintf(buf, "%f", val);
    retStr = buf;
    return retStr;
}

string Utilities::MkTempDir()
{
    string tmpdir;

    int trials=0;
    do {
        tmpdir = string(P_tmpdir) + "/amygdala-" +
                 itostr(1+(int) (1000.0*rand()/(RAND_MAX+1.0)));
        if(++trials > 10)
            throw runtime_error("cannot create temp directory: " + tmpdir);
    } while (mkdir(tmpdir.c_str(), S_IRUSR | S_IWUSR | S_IXUSR));
    return tmpdir;
}