eval3d
======

values of a function on a grid



Calling Sequence
~~~~~~~~~~~~~~~~


::

    [z]=eval3d(fun,x,[y])




Arguments
~~~~~~~~~

:fun function accepting vectors as arguments.
: :x,y 2 vectors of size (1,n1) and (1,n2). (default value for `y` :
  `y=x`).
: :z matrix of size (n1,n2).
:



Description
~~~~~~~~~~~

This function returns a matrix `z(n1,n2)`. `z(i,j)=fun(x(i),y(j))`. If
the function `fun` does not accept arguments of type vector use the
primitive `feval`.



Sample
~~~~~~



Examples
~~~~~~~~


::

    x=-5:5;y=x;
    `deff`_('[z]=f(x,y)',['z= x.*y']);
    z=eval3d(f,x,y);
    `plot3d`_(x,y,z);
    
    `deff`_('[z]=f(x,y)',['z= x*y']);
    z=`feval`_(x,y,f);
    `plot3d`_(x,y,z);




See Also
~~~~~~~~


+ `feval`_ multiple evaluation


.. _feval: feval.html