Plotting a 3D graph, incorrect solution.

    clc
clear
  p00 =       553.6;
       p10 =       23.56;
       p01 =      -24.72;
       p20 =       212.1;
       p11 =      -301.9;
       p02 =       186.9;
       p30 =       -2.76;
       p21 =      -1.261;
       p12 =      -7.603;
       p03 =       11.23;
       p40 =      -54.55;
       p31 =        30.5;
       p22 =       10.44;
       p13 =       36.48;
       p04 =      -48.45;
       m=1;
       n=1;
for x=-100:1:100
    n=1;
    for y=-100:1:100
Z(m,n)=p00+p10*x+p01*y+p20*x^2+p11*x*y+p02*y^2+p30*x^3+p21*x^2*y+p12*x*y^2+p03*x^3+p40*x^4+p31*y^3*y+p22*y^2*x^2+p13*x*y^3+p04*y^4
    n=n+1;
    end
    m=m+1;
end
surf(x,y,Z)
title('3D PLOT'),xlabel('\bfX'),ylabel('\bfY'),zlabel('\bfZ')

This is the code that gets the Z array, which is to be plotted. Rewriting this in vectorised form, I have

   clc
clear
x=-100:1:100;
y=-100:1:100;
  p00 =       553.6;
       p10 =       23.56;
       p01 =      -24.72;
       p20 =       212.1;
       p11 =      -301.9;
       p02 =       186.9;
       p30 =       -2.76;
       p21 =      -1.261;
       p12 =      -7.603;
       p03 =       11.23;
       p40 =      -54.55;
       p31 =        30.5;
       p22 =       10.44;
       p13 =       36.48;
       p04 =      -48.45;
[X Y]=meshgrid(x,y);
Z=p00+p10*X+p01*Y+p20*X^2+p11*X*Y+p02*Y^2+p30*X^3+p21*X^2*Y+p12*X*Y^2+p03*Y^3+p40*X^4+p31*X^3*Y+p22*X^2*Y^2+p13*X*Y^3+p04*Y^4
surf(X,Y,Z)
title('3D PLOT'),xlabel('\bfX'),ylabel('\bfY'),zlabel('\bfZ')

Why am I getting separate solutions for both, when the solution should be the one that I am getting from the second one. (solution here is the values in Z). Any help would be most appreciated.

Solved, I was not putting the dots before the product and power operators.

Answer 1

[Seyedali Mirjalili]

The problem is that after exiting the for loops, x and y are both equal to 100. So, they are scalars and cannot be used in surf. The function surf requires 2D matrices.

[Pulkit Sharma]

So, I do I use the surf option to plot that function?