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Discussion Groups | Matlab DSP | how to tell if variable is defined


Technical discussion about Matlab and issues related to Digital Signal Processing.

  

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how to tell if variable is defined - toanxtoan - Jul 1 10:04:24 2006

say i type in

>> a
??? Undefined function or variable 'a'.

is there a T/F test for which i can tell whether a var is defined?





Re: how to tell if variable is defined - Nandan Das - Jul 2 12:32:54 2006

use the command "exist"

Nandan

help exist
 EXIST  Check if variables or functions are defined.
    EXIST('A') returns:
      0 if A does not exist
      1 if A is a variable in the workspace
      2 if A is an M-file on MATLAB's search path.  It also returns 2 when
           A is the full pathname to a file or when A is the name of an
           ordinary file on MATLAB's search path
      3 if A is a MEX- or DLL-file on MATLAB's search path
      4 if A is a MDL-file on MATLAB's search path
      5 if A is a built-in MATLAB function
      6 if A is a P-file on MATLAB's search path
      7 if A is a directory
      8 if A is a Java class

On 6/30/06, toanxtoan <h...@gmail.com> wrote:
>
> say i type in
>
> >> a
> ??? Undefined function or variable 'a'.
>
> is there a T/F test for which i can tell whether a var is defined?
>