miscmaths.cc

/*  miscmaths.cc

    Mark Jenkinson & Mark Woolrich & Christian Beckmann, FMRIB Image Analysis Group

    Copyright (C) 1999-2000 University of Oxford  */

/*  CCOPYRIGHT  */

// Miscellaneous maths functions

#include "miscmaths.h"
#include "stdlib.h"

using namespace std;

namespace MISCMATHS {

  // The following lines are ignored by the current SGI compiler
  //  (version egcs-2.91.57)
  // A temporary fix of including the std:: in front of all abs() etc
  //  has been done for now
  using std::abs;
  using std::sqrt;
  using std::exp;
  using std::log;
  //  using std::pow;
  using std::atan2;

  // General string/IO functions

  bool isnum(const string& str)
  {
    // assumes that initial whitespace has been removed
    if (isdigit(str[0])) return true;
    if ( (str[0]=='-') || (str[0]=='+') || (str[0]=='.') )  return true;
    return false;
  }
    
  string skip_alpha(ifstream& fs) 
  {
    string cline;
    while (!fs.eof()) {
      getline(fs,cline);
      cline += " "; // force extra entry in parsing
      istrstream ss(cline.c_str());
      string cc="";
      ss >> cc;
      if (isnum(cc)) {
	fs.seekg(-((int)cline.size()),ios::cur);
	return cline;
      }
    }
    return "";
  }

  ReturnMatrix read_ascii_matrix(int nrows, int ncols, const string& filename)
  {
    return read_ascii_matrix(filename,nrows,ncols);
  }


  ReturnMatrix read_ascii_matrix(const string& filename, int nrows, int ncols)
  {
    Matrix mat(nrows,ncols);
    mat = 0.0;
  
    if ( filename.size()<1 ) return mat;
    ifstream fs(filename.c_str());
    if (!fs) { 
      cerr << "Could not open matrix file " << filename << endl;