[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: How to share variables between functions

From: Guillem Borrell Nogueras
Subject: Re: How to share variables between functions
Date: Tue, 3 Apr 2007 16:14:46 +0200
User-agent: KMail/1.9.5

Most of times the code becomes simpler using anonymous functions via function 
handles like `y=@(x,t) ...`.  This is a very useful trick in Matlab where 
every function means yet another .m file.  The anonymous functions have the 
interesting property of catching all the variables in their space:

. >>a=2;
. >>f = @(x) x*a;
. >>f(3)
ans = 6

is legal and keeps the variable "a" in the main workspace.  Try to rewrite 
your code using this trick and maybe there will be no need of using any 
global variable.  This is the recommended way in matlab's documentation.

NOTE: the anonymous functions work this way in octave 2.9.  Octave 2.1 will 
complain saying that the variable "a" is unknown.

On Tuesday 03 April 2007 07:38, Evan wrote:
> In some cases, it seems that sharing variables between functions
> cannot be avoidable. for example
> function y=f(x)
>     global x;
>     y=quad(subf,0,1);
>     clear x;
> endfunction
> function f=subf(t)
>     global x;
>     f=g(x,t);
> endfunction
> function y=g(x,t)
>     ......
> endfunction
> because "quad" function only accept functions with one scalar
> argument, other arguments have to be passed by other means. The only
> way I know is to use global variables as the above example does. But I
> don't think it is a good idea for that the variable "x" would also be
> accessible elsewhere, thus confusion may be caused. Is there any
> method to share local variables between functions, that is, these
> variables are not visible elsewhere?
> Thanks in advance
> _______________________________________________
> Help-octave mailing list
> address@hidden

reply via email to

[Prev in Thread] Current Thread [Next in Thread]