Programming and Graphics

232 Introduction to C++ Programming and Graphics

float xd[n], yd[n]; // data points

float t=0.; // time

float Dt=0.05; // time step

for (int i=0; i<n; i++)

{

xd[i]=(i-1.0)/n; // abscissas

}

//--- Plotting parameters:

float xmin=0.0, xmax=1.0; // plotting limits

float ymin=0.0, ymax=1.0;

int ntcx =10; // number of ticks on the x axis

int ntcy =10; // number of ticks on the y axis

int Ilabelax =1; // 1 to label axes; 0 for no labels

int axc = BLACK; // axis color

int lbc = RED; // plot label color

char labelx[] = "x"; // x-axis label

char labely[] = "y"; // y-axis label

char title1[] =" "; // // first plot label

char title2[] =" "; // // second plot label

char title3[] =" ";// // third plot label

//--- Graphics:

float xmarg = 0.2*(xmax-xmin); // plotting margin

float ymarg = 0.2*(ymax-ymin);

int Icheck;

again:

prefposition (500,100);

prefsize (500,500);

vinit ("X11");

backbuffer();

short Itry = 0;

short Iplot = 0;

repeat:

ortho2 (xmin-xmarg,xmax+xmarg,ymin-ymarg,ymax+ymarg);

color (WHITE);

clear();

//--- Repaint the plotting area:

if(Iplot==4 || Iplot==6)