/*
Eliza Dubroff
ps7#1
4/24/97
layer.cc
*/

#include <math.h>
#include "layer.h"

#define numterms 3

void layer::find_volume(void)
{
 double t[numterms], w[numterms];
 double x;
 double y;
 double d1;
 double I1, I2=0;

 t[0] = -0.77459667;
 t[1] = 0;
 t[2] = 0.77459667;

 w[0] = 0.55555555;
 w[1] = 0.88888889;
 w[2] = w[0];

 for(int i=0;i<numterms;i++)
   {
     I1=0;
     y=((large*(1+t[i]))/2);
     for(int j=0;j<numterms;j++)
      {
	x=(wide*(1+t[j]))/2;
        d1=height(x,y);
	I1=I1+(w[j]*d1);
      }
     I1=I1;
     I2=I2+w[i]*I1;
   }
 I2=I2*wide*large/4;
 volume=I2;
}