Conditional Plotting

Hi all,

I would like to plot the following graph only for the range where y2=>y1, leaving Z for y1>y2 empty.

y1=0:0.01:1;

y2=0:0.01:1;

[Y1,Y2]=meshgrid(y1,y2);

Z=((Y1 - Y2).*(Y1.^2 + 4*Y1.*Y2 - 6*Y1 + 7*Y2.^2 - 18*Y2 + 12))/12;

surf(Y1,Y2,Z)

xlabel('Y1')

ylabel('Y2')

How can I do this? Many thanks for any help. David

Answer 1

[Jonathan Sullivan]

y1=0:0.01:1;
y2=0:0.01:1;
[Y1,Y2]=meshgrid(y1,y2);
Z=((Y1 - Y2).*(Y1.^2 + 4*Y1.*Y2 - 6*Y1 + 7*Y2.^2 - 18*Y2 + 12))/12;
Z(Y1 > Y2) = NaN;
surf(Y1,Y2,Z)
xlabel('Y1')
ylabel('Y2')

[old_user_rat]

Great, thanks