cag++.cpp

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/*! 
 * \file 
 * This is the cagniard algorithm to calculate synthetic 1D forward responses for MT.
 *  It reads in model files in the following simple format:
 * <TABLE>
 * <TR> <TD> No. of layers </TD> </TR>
 * <TR> <TD> Thickness in km </TD>  <TD> Resistivity in \f$\Omega m\f$  </TD></TR>
 * </TABLE>
 * 
 * The user has to specify the output filename without the ending. ".mtt" will be appended
 * automatically to indicate that this file is in Goettingen .mtt format.
 * 
 * There are two different modes: In standard mode (mode 0)
 * the frequencies at which the responses are 
 * calculated are based on some realistic frequencies used in deep MT surveys (300Hz - 10.000s).
 * In mode 1 the user can specify a window length and sampling rate and the output frequencies are
 * based on the fft of a windows with those parameters. This is only useful for some special 
 * processing applications and might be removed in the future.
 */

#include <iostream>
#include <string>
#include "Util.h"
#include "C1DMTSynthData.h"
#include <iterator>

using namespace std;

int main(int argc, char *argv[]) {
        string version =
                        "$Id: cag++.cpp 20 2005-11-11 12:57:01 +0100 (Fr, 11 Nov 2005) max $";
        cout << endl << endl;
        cout << "Program " << version << endl;
        cout << "Calculates 1D MT Responses from input models " << endl;
        cout
                        << "Based on Cagniard algorithm, with stability enhancements taken from A. Avdeeva "
                        << endl;

        C1DMTSynthData Synthetic; // create Object for Calculation of Synthetics


        double samplerate, freqstep;
        int samplelength;
        const double eps = 1e-5;
        string modelfilename, mttfilename;
        int mode = 0;
        try
        {
                if (argc == 2)
                {
                        modelfilename = argv[1];
                        mttfilename = modelfilename;
                        mode = 0;
                }
                else
                {
                        modelfilename = AskFilename("Model filename: ");

                        cout << "Output Format is .mtt ! Do not append ending. " << endl;
                        mttfilename = AskFilename("Output filename: ");

                        cout << "Use Mode = 0 for standard calculation" << endl;
                        cout << "Use Mode = 1 if you want frequencies to be calculated from sample rate and window length." << endl;
                        cout << "Mode: ";
                        cin >> mode;
                }
                Synthetic.ReadModel(modelfilename); // read in model
                if (mode == 1) //if we want frequencies for a certain window length and sampling rate
                {
                        cout << "Sampling rate: "; //ask
                        cin >> samplerate;
                        cout << "Length for continuous sample: ";
                        cin >> samplelength;
                        freqstep = samplerate/samplelength;
                        trealdata frequency;
                        frequency.push_back(eps); //zero frequency means not valid so we use a small value for the static
                        for (int i = 1; i < samplelength/2; ++i) // add frequencies
                        {
                                frequency.push_back(freqstep * i);
                        }
                        Synthetic.SetFrequencies(frequency);//copy them to forward calculation object
                }

                Synthetic.GetData(); // Calculate Model
                Synthetic.WriteAsMtt(mttfilename); // Write out Mtt file
        }
        catch(CFatalException &e)
        {
                cerr << e.what() << endl;
                return -1;
        }
}

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