function [x_vec,y_vec] = quad_fcn(a,b,c,x_min,x_max,delta_x)
%
%   Calculates the value of a quadratic 
%   y = a*x^2 + b*x + c
%   for x from x_min to x_max, in increments of delta_x.
%   The value of x is stored in the vector x_vec
%   and the value of y is stored in the vector y_vec.
%
row = 0 ;
for x = x_min:delta_x:x_max
    row = row + 1;
    y = a * x^2 + b * x + c;
    x_vec(row,1) = x;
    y_vec(row,1) = y;
end




