[Octave-bug-tracker] [bug #53220] Sending strings to quadl

[Rik]

Follow-up Comment #3, bug #53220 (project octave):

The quad error message is different because it can actually accept raw code to
execute, rather than the documented first argument for all the other quad
functions:


F is a function handle, inline function, or string containing the
name of the function to evaluate


For example,


quad ("x.^2 + 1", 0, 2)
warning: quad: passing function body as a string is obsolete; please use
anonymous functions
ans =  1.3333


Try the same thing with quadl and you get 


quadl ("x.^2 + 1", 0, 2)
error: feval: function 'x.^2 + 1' not found


because it recognizes that the double-quoted object is a string, and therefore
should be the name of a function.

Accordingly, you can either give it a function handle, inline function, or
name of a function that calculates what you want.


octave:5> function y = MYF (x)
> y = x.^2 + 1;
> endfunction
octave:6> quadl ("MYF", 0, 1)
ans =  1.3333
octave:7> quadl (@(x) x.^2 + 1, 0, 1)
ans =  1.3333
octave:8> quadl (inline ("x.^2 + 1"), 0, 1)
ans =  1.3333




    _______________________________________________________

Reply to this item at:

  <http://savannah.gnu.org/bugs/?53220>

_______________________________________________
  Message sent via/by Savannah
  http://savannah.gnu.org/