//
//Prelab4_2.sce
//
//This program will use trapezoind rule to approximate the
//integral of a function.
//
//By:  M. Coburn, J. Wireman
//

//Defintion of the function to be integrated
function foo = f(x)
	foo = 5*x + sin(9*x - 5)/x
endfunction

//Set the time length and step size
t_start = 1;
t_end = 9;
subs = 1000;
delta_x = (t_end - t_start)/subs;


//This loop uses the trapezoid rule to approximate the integral of the function
//on the interval defined above.

total = 0;
for i = 0:subs,
	x = t_start + i*delta_x;
	if i == 0 then
		total = total + f(x);
	elseif i == subs then
		total = total + f(x);
	else total = total + 2*f(x);

	end
end

total = total * delta_x/2;
printf("The approximate value of the integral is %f\n", total);