Different behaviour of function handles in matlab and octave

[Guillem Borrell Nogueras]

Hi

Playing with the interp1 function in matlab and octave i've found that the anonymous functions have different behaviours in the two interpreters.

In Matlab you can use anonymous functions to reduce the number of variables and to simplify one function, for instance:

>> x=[1 2 3 4 5 6 7 8];

>> y=[2 3 4 3 6 7 5 7];

>> newfunc=@(z) interp1(x,y,z,'spline');

>> newfunc(4.444)

ans =

4.0376

But anonymous functions in octave don't look for variables outside the function handle itself

>> x=[1 2 3 4 5 6 7 8];

>> y=[2 3 4 3 6 7 5 7];

>> newfunc=@(z) interp1(x,y,z,'spline');

>> newfunc(4.444)

error: `x' undefined near line 3 column 22

error: evaluating argument list element number 1

error: called from `?unknown?'

>>

You must define all the variables in the "heading"

>> newfunc=@(x,y,z) interp1(x,y,z,'spline');

>> newfunc(x,y,4.444)

ans = 4.0376

¿Is this a missing feature or is it a difference between the two interpreters?

thanks

guillem

--

Guillem Borrell Nogueras

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