what is better matlab function or symfun

in drawing a f(x,y)=0 which would be better...

syms f(x,y)
f=x^2+y^2
fimplicit(f)
or
f=@(x,y) x^2+y^2
fimplicit(f)

Answer 1

[Star Strider]

Neither plot works with your code. Try fcontour instead.

Otherwise, you have to vectorise your anonymous function for it to work without error:

f=@(x,y) x.^2+y.^2

The symfun version works without modification. If you want to use it as an anonymous function without having to vectorise it yourself, use the matlabFunction function:

syms f(x,y)
f=x^2+y^2-1
figure(1)
fimplicit(f, [-10 10],'bp')

f=matlabFunction(f)
figure(2)
fimplicit(f)

I added the ‘-1’ so it will actually plot something.