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#include<math.h>
#include<stdio.h>
#include<conio.h>
#include<iostream>
using namespace std;
double f1(double x, double u, double y, double z, double w, double p)
{
return y;
}
//
double f2(double x, double u, double y, double z, double w, double p)
{
return z;
}
//
double f3(double x, double u, double y, double z, double w, double p)
{
return -3 * u*z + 2 * y*y - w;
}
//
double f4(double x, double u, double y, double z, double w, double p)
{
return p;
}
double f5(double x, double u, double y, double z, double w, double p)
{
return -2.25*u*p;
}
//
int main(void){
const double EPS = 1e-10;
int i, n = 40;
double h;
//
h = 10.0 / n;
//
double *x;
x = new double[n + 1];
x[0] = 0.0;
//
for (i = 0; i<n + 1; i++)
x[i] = i*h;
void Outputofarray(double x[], int n);
{
printf("\n");
for (i = 0; i<n + 1; i++)
{
cout << x[i] << endl;
}
}
//
cout << "step in the coordinate h= " << h << endl;
//
double *u;
u = new double[n + 1];
u[0] = 0.0;
double *y;
y = new double[n + 1];
y[0] = 0.0;
double *z;
z = new double[n + 1];
z[0] = 7.0;
double *w;
w = new double[n + 1];
w[0] = 1.0;
double *p;
p = new double[n + 1];
p[0] = -3.0;
//
int iter;
//
double ksi = 0.0, eta = 7.0, gamma = 1.0, epsilon = -3.0;
double hy, hw, dd, dy, dw;
double bb, cc, bby, ccy, bbw, ccw;
double a1, a2, a3, a4;
double b1, b2, b3, b4;
double c1, c2, c3, c4;
double d1, d2, d3, d4;
double g1, g2, g3, g4;
iter = 0;
do
{
iter++;
u[0] = 0.0;
y[0] = ksi;
z[0] = eta;
w[0] = gamma;
p[0] = epsilon;
//
for (i = 0; i<n; i++)
{
a1 = f1(x[i], u[i], y[i], z[i], w[i], p[i])*h;
b1 = f2(x[i], u[i], y[i], z[i], w[i], p[i])*h;
c1 = f3(x[i], u[i], y[i], z[i], w[i], p[i])*h;
d1 = f4(x[i], u[i], y[i], z[i], w[i], p[i])*h;
g1 = f5(x[i], u[i], y[i], z[i], w[i], p[i])*h;
//
a2 = f1(x[i] + 0.5*h, u[i] + 0.5*a1, y[i] + 0.5*b1, z[i] + 0.5*c1, w[i] + 0.5*d1, p[i] + 0.5*g1)*h;
b2 = f2(x[i] + 0.5*h, u[i] + 0.5*a1, y[i] + 0.5*b1, z[i] + 0.5*c1, w[i] + 0.5*d1, p[i] + 0.5*g1)*h;
c2 = f3(x[i] + 0.5*h, u[i] + 0.5*a1, y[i] + 0.5*b1, z[i] + 0.5*c1, w[i] + 0.5*d1, p[i] + 0.5*g1)*h;
d2 = f4(x[i] + 0.5*h, u[i] + 0.5*a1, y[i] + 0.5*b1, z[i] + 0.5*c1, w[i] + 0.5*d1, p[i] + 0.5*g1)*h;
g2 = f5(x[i] + 0.5*h, u[i] + 0.5*a1, y[i] + 0.5*b1, z[i] + 0.5*c1, w[i] + 0.5*d1, p[i] + 0.5*g1)*h;
//
a3 = f1(x[i] + 0.5*h, u[i] + 0.5*a2, y[i] + 0.5*b2, z[i] + 0.5*c2, w[i] + 0.5*d2, p[i] + 0.5*g2)*h;
b3 = f2(x[i] + 0.5*h, u[i] + 0.5*a2, y[i] + 0.5*b2, z[i] + 0.5*c2, w[i] + 0.5*d2, p[i] + 0.5*g2)*h;
c3 = f3(x[i] + 0.5*h, u[i] + 0.5*a2, y[i] + 0.5*b2, z[i] + 0.5*c2, w[i] + 0.5*d2, p[i] + 0.5*g2)*h;
d3 = f4(x[i] + 0.5*h, u[i] + 0.5*a2, y[i] + 0.5*b2, z[i] + 0.5*c2, w[i] + 0.5*d2, p[i] + 0.5*g2)*h;
g3 = f5(x[i] + 0.5*h, u[i] + 0.5*a2, y[i] + 0.5*b2, z[i] + 0.5*c2, w[i] + 0.5*d2, p[i] + 0.5*g2)*h;
//
a4 = f1(x[i] + h, u[i] + a3, y[i] + b3, z[i] + c3, w[i] + d3, p[i] + g3)*h;
b4 = f2(x[i] + h, u[i] + a3, y[i] + b3, z[i] + c3, w[i] + d3, p[i] + g3)*h;
c4 = f3(x[i] + h, u[i] + a3, y[i] + b3, z[i] + c3, w[i] + d3, p[i] + g3)*h;
d4 = f4(x[i] + h, u[i] + a3, y[i] + b3, z[i] + c3, w[i] + d3, p[i] + g3)*h;
g4 = f5(x[i] + h, u[i] + a3, y[i] + b3, z[i] + c3, w[i] + d3, p[i] + g3)*h;
//
u[i + 1] = u[i] + (a1 + 2.0*a2 + 2.0*a3 + a4) / 6.0;
y[i + 1] = y[i] + (b1 + 2.0*b2 + 2.0*b3 + b4) / 6.0;
z[i + 1] = z[i] + (c1 + 2.0*c2 + 2.0*c3 + c4) / 6.0;
w[i + 1] = w[i] + (d1 + 2.0*d2 + 2.0*d3 + d4) / 6.0;
p[i + 1] = p[i] + (g1 + 2.0*g2 + 2.0*g3 + g4) / 6.0;
}
//
bb = y[n] - 0.0;
cc = w[n] - 0.0;
cout << "bb " << bb << " cc " << cc << endl;
for (i = 0; i<n + 1; i++)
{
cout << "x[i]= " << x[i] << " then u[i]= " << u[i] << endl;
cout << "x[i]= " << x[i] << " then y[i]= " << y[i] << endl;
cout << "x[i]= " << x[i] << " then z[i]= " << z[i] << endl;
cout << "x[i]= " << x[i] << " then w[i]= " << w[i] << endl;
cout << "x[i]= " << x[i] << " then p[i]= " << p[i] << endl;
delete[] x;
delete[] u;
delete[] y;
delete[] z;
delete[] w;
delete[] p;
system("pause");
}
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