Why isn't my line visible on this graph?

function main

t = 0:0.5:2*pi;
p = 0:0.5:pi;
[T,P] = meshgrid(t,p);

sphr(1,0,0,0)
hold on
circ(2,0,0)
hold off

function s = sphr(r,a,b,c)
x = r.*cos(T).*sin(P)+a;
y = r.*sin(T).*sin(P)+b;
z = r.*cos(P)+c;
surf(x,y,z)
end

function c = circ(r,a,b)
x = r.*cos(T)+a;
y = r.*sin(T)+b;
line(x,y);
end

end

Answer 1

[Edgar Guevara]

Hi lmhall,

The circle should be defined as a function of a vector (small t), not the 2-Dgrid (capital T), so, pleace replace the following lines in your code:

x = r.*cos(T)+a;
y = r.*sin(T)+b;

with:

x = r.*cos(t)+a;
y = r.*sin(t)+b;

and you'll see the line.

Hope it helps,

Edgar