fnchg
Change part(s) of form
Syntax
f = fnchg(f,part,value) 
Description
f = fnchg(f,part,value)  returns the given
                function description f but with the specified
                    part changed to the specified
                value.
The character vector or string scalar part can be (the
                beginning character(s) of) :
| 
 | The dimension of the function's target | 
| 
 | The basic interval of that form | 
The specified value for part is not checked
                for consistency with the rest of the description in f in case the
                character vector or string scalar part terminates with the letter
                    z.
Examples
fndir(f,directions) returns a vector-valued function even when
                the function described by f is ND-valued. You can correct this by
                using fnchg as follows:
fdir = fnchg( fndir(f,directions),...
           'dim',[fnbrk(f,'dim'),size(directions,2)] );