From help-octave-request at bevo dot che dot wisc dot edu  Thu Feb 15 18:18:37 2001
Subject: Re: extract from cell?
From: Paul Kienzle <pkienzle at kienzle dot powernet dot co dot uk>
To: Daniel Heiserer <Daniel dot Heiserer at bmw dot de>
Cc: "help-octave at bevo dot che dot wisc dot edu" <help-octave@bevo.che.wisc.edu>
Date: Thu, 15 Feb 2001 17:20:56 +0000

You could use the following untested function based on nth from ov-list.cc:

- Paul

DEFUN (cellget, args, ,
  "-*- texinfo -*-\n\
 at deftypefn {Built-in Function} {} nth (@var{cellget}, @var{i}, @var{j})\n\
Return the  at var{i,j}-th element of @var{cell}.\n\
 at end deftypefn")
{
  octave_value retval;
  int i=-1,j=-1;
  
  if (args.length() < 2 || args.length() > 3)
    {
      print_usage ("nth");
      return retval;
    }
  
  i = args(1).int_value (true);
  if (error_state || i < 1)
    {
      error ("cellget: second argument must be a positive integer");
      return retval;
    }
  
  if (args.length() == 3) 
    {
      j = args(2).int_value (true);
      if (error_state || j < 1)
	{
	  error ("cellget: third argument must be a positive integer");
	  return retval;
	}
    }
  
  Cell cell = args(0).cell_value ();
  
  if (! error_state)
    {
      int nr = cell.rows();
      int nc = cell.columns();
      
      if (j == -1) 
	if (nr == 1)
	  if (i <= nc)
	    retval = cell(0,i-1);
	  else
	    error ("cellget: index = %d out of range", i);
	else if (nc == 1)
	  if (i <= nr)
	    retval = cell(i-1,0);
	  else
	    error ("cellget: index = %d out of range", i);
	else
	  error ("cellget: single index not valid for 2-D cell array");
      else if (i <= nr && j <= nc)
	retval = cell(i-1, j-1);
      else
	error ("cellget: index = %d,%d out of range", i, j);
    }
  else
    error ("cellget: first argument must be a list or cell");

  return retval;
}

On Thu, Feb 15, 2001 at 05:47:56PM +0100, Daniel Heiserer wrote:
> How can I get a matrix I put into a cell?
> Whatever operation I apply the cell returns a cell.
> I need the basic datatype somewhen.
> 
> thanks daniel
> 
> octave-2.1.31:6> a={1,rand(3),'jonny'}
> a =
> {
>   [1,1] = 1
>   [1,2] =
> 
>     0.14950  0.69857  0.99893
>     0.49560  0.54115  0.17106
>     0.32942  0.34194  0.17245
> 
>   [1,3] = jonny
> }
> octave-2.1.31:7> b=a(1,2)
> b =
> {
>   [1,1] =
> 
>     0.14950  0.69857  0.99893
>     0.49560  0.54115  0.17106
>     0.32942  0.34194  0.17245
> 
> }
> 
> Thanks daniel
Content-Description: Card for Daniel Heiserer



-------------------------------------------------------------
Octave is freely available under the terms of the GNU GPL.

Octave's home on the web:  http://www.octave.org
How to fund new projects:  http://www.octave.org/funding.html
Subscription information:  http://www.octave.org/archive.html
-------------------------------------------------------------