BaseInput.h

/*
        Copyright (C) 2004  Timothy C.A. Molteno
        
        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.
        
        This program is distributed in the hope that it will be useful,
        but WITHOUT ANY WARRANTY; without even the implied warranty of
        MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
        GNU General Public License for more details.
        
        You should have received a copy of the GNU General Public License
        along with this program; if not, write to the Free Software
        Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/
#pragma once
 
#include "math_util.h"
 
#include <algorithm>
#include <cmath>
#include <fstream>
#include <sstream>
 
/* Relative difference of two values, normalised by the larger magnitude.
   The scale test must use magnitudes: comparing signed values against the
   1e-8 floor treats any two negative numbers as "effectively zero". */
nec_float diff(nec_float a, nec_float b)
{
        if (a == b)
                return 0;
 
        nec_float scale = std::max(std::fabs(a), std::fabs(b));
        if (scale < 1e-8)
                return 0;
 
        nec_float ret = std::fabs(a - b) / scale;
        if (ret > 1e-2)
        {
                cout << "    diff(" << a << "," << b << ") = " << ret << endl;
        }
        return ret;
}
 
nec_float diff(nec_complex a, nec_complex b)
{
        if (a == b)
                return 0;
 
        nec_float scale = std::max(abs(a), abs(b));
        if (scale < 1e-8)
                return 0;
 
        nec_float ret = abs(a - b) / scale;
        if (ret > 1e-2)
        {
                stringstream ss;
                cout << "    diff(" << a << "," << b << ") = " << ret << endl;
        }
        return ret;
}
 
class BaseInput
{
public:
        BaseInput(const std::string& filename)
                :       m_filename(filename),
                        m_stream(filename.c_str())
        {
        }
        
private:
        char linec[512];
 
 
protected:
 
        std::string m_filename;
        std::ifstream m_stream;
        
        string readline()
        {
                m_stream.getline(&linec[0],512);
                return string(&linec[0]);
        }
 
        double read_sci(std::istream& is)
        {
                double x = 0.0; /* zero on extraction failure (was returned uninitialized) */
                is.setf(ios_base::skipws);
                is >> x;
                return x;
        }
 
        double read_fixed(std::istream& is)
        {
                double x = 0.0; /* zero on extraction failure (was returned uninitialized) */
                is.setf(ios_base::skipws);
                is >> x;
                return x;
        }
};