Constructing Chebfun2 from slightly non-smooth chebfun seems not working

[Mike]

Hello friends!

I have a very simple question (I think!) but surprisingly it does not work. I would like to make a chebfun2

function which is made of a chebfun function where the later is not smooth. Consider the following:

>> f=chebfun({0,@(x)sin(x)},[-2 0 2],'vectorize');
>> g=chebfun(@(y)y,[0 3],'vectorize');
>> h=chebfun2(@(x,y)f(x)*g(y),[-2 2 0 3],'vectorize');

I did try both splitting on and off options. I wait a lot and at the end neighter I get error message nor I get any solution.

Thanks for your response!

Very best,

Babak

[Nick Trefethen]

Chebfun2 is made for smooth functions, so this won't work.  However, you can get a reasonable approximation by forcing it to take a grid of a fixed size.  For example, here I make the grid of size 100 x 100:

```

>> f=chebfun({0,@(x)sin(x)},[-2 0 2]);
>> g=chebfun(@(y)y,[0 3]);
>> h=chebfun2(@(x,y)f(x).*g(y),[-2 2 0 3],[100,100]);
>> surf(h), camlight

```

The plot is below.