119 lines
2.7 KiB
C++
119 lines
2.7 KiB
C++
|
/* rk4.cc - Simulation of rocket flight */
|
||
|
|
/* Copyright (C) 2000 */
|
||
|
|
/* Antoine Lefebvre <antoine.lefebvre@polymtl.ca> */
|
||
|
|
|
||
|
|
/* 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., 675 Mass Ave, Cambridge, MA 02139, USA. */
|
||
|
|
|
||
|
|
#include <stdlib.h>
|
||
|
|
#include <stdio.h>
|
||
|
|
|
||
|
|
#include <cmath>
|
||
|
|
#include <iostream>
|
||
|
|
#include <fstream.h>
|
||
|
|
|
||
|
|
#include "rk4.h"
|
||
|
|
#include "c++rocket.h"
|
||
|
|
|
||
|
|
|
||
|
|
static int ModelNeq[MODEL_LAST] = { 7, 5 };
|
||
|
|
|
||
|
|
|
||
|
|
rk4_solver::rk4_solver(Model_t model)
|
||
|
|
{
|
||
|
|
neq = ModelNeq[model];
|
||
|
|
time = 0.0;
|
||
|
|
memory = 0;
|
||
|
|
|
||
|
|
switch (model)
|
||
|
|
{
|
||
|
|
case AERO_MODEL:
|
||
|
|
md = model_1;
|
||
|
|
break;
|
||
|
|
case SIMPLE_MODEL:
|
||
|
|
md = model_2;
|
||
|
|
break;
|
||
|
|
default:
|
||
|
|
exit(-1);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
rk4_solver::~rk4_solver()
|
||
|
|
{
|
||
|
|
if (memory) {
|
||
|
|
for (int j = 0; j < length; j++)
|
||
|
|
delete [] ans[j];
|
||
|
|
delete ans;
|
||
|
|
}
|
||
|
|
cout << "Freeing memory...\n" ;
|
||
|
|
}
|
||
|
|
|
||
|
|
int rk4_solver::solve(double *st, double duration, double step)
|
||
|
|
{
|
||
|
|
int i;
|
||
|
|
|
||
|
|
length = (int)rint(duration/step) + 1;
|
||
|
|
|
||
|
|
// memory allocation
|
||
|
|
ans = new double*[length];
|
||
|
|
for (int j = 0; j < length; j++)
|
||
|
|
ans[j] = new double[neq];
|
||
|
|
|
||
|
|
memory = 1;
|
||
|
|
|
||
|
|
// fill the ans array
|
||
|
|
rk4 ( (ModelFunc_t)md, neq, step, duration, st, ans, NULL);
|
||
|
|
return length;
|
||
|
|
}
|
||
|
|
|
||
|
|
// print the data to screen
|
||
|
|
void rk4_solver::print()
|
||
|
|
{
|
||
|
|
for (int i = 0; i < length; i++)
|
||
|
|
{
|
||
|
|
for (int j = 0; j < neq; j++)
|
||
|
|
{
|
||
|
|
cout << ans[i][j] << "\t";
|
||
|
|
}
|
||
|
|
cout << "\n";
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// export the data in filename with the format need by octave
|
||
|
|
// for the function load. It will maybe work with matlab to
|
||
|
|
// but i'm not sure
|
||
|
|
void rk4_solver::export_octave(char *filename)
|
||
|
|
{
|
||
|
|
|
||
|
|
ofstream out(filename);
|
||
|
|
|
||
|
|
out << "# Create by c++rocket" << endl;
|
||
|
|
out << "# name: M" << endl;
|
||
|
|
out << "# type: matrix" << endl;
|
||
|
|
out << "# rows: " << length << endl;
|
||
|
|
out << "# columns: " << neq << endl;
|
||
|
|
|
||
|
|
for (int i = 0; i < length; i++)
|
||
|
|
{
|
||
|
|
for (int j = 0; j < neq; j++)
|
||
|
|
{
|
||
|
|
out << ans[i][j] << " ";
|
||
|
|
}
|
||
|
|
out << endl;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
|