From bug-octave-request at bevo dot che dot wisc dot edu Tue Dec 16 18:37:02 2003
Subject: [] & [] fails
From: "John W. Eaton" <jwe at bevo dot che dot wisc dot edu>
To: Paul Kienzle <pkienzle at users dot sourceforge dot net>
Cc: bug-octave at bevo dot che dot wisc dot edu
Date: Tue, 16 Dec 2003 18:36:46 -0600

On 16-Dec-2003, John W. Eaton <jwe at bevo dot che dot wisc dot edu> wrote:

| The following patch should fix the crash.  The find function still
| needs to be made N-d aware.

I fixed the find function in CVS so that it can handle N-d arrays.

I also added sub2ind and ind2sub functions that are N-d aware.  I
based parts of them on the octave-forge code, but decided not to
handle matrix args or return values specially because it leads to
incompatibilities with Matlab.  For example, Matlab allows all of
these:

	      ind2sub ([3,4,5], [2,3,4,5])
  [i,j]     = ind2sub ([3,4,5], [2,3,4,5])
  [i,j,k]   = ind2sub ([3,4,5], [2,3,4,5])
  [i,j,k,l] = ind2sub ([3,4,5], [2,3,4,5])

In the first case, ind2sub behaves as if the dimensions are [60,1].
In the second, it behaves as as if the dimensions are [3,20].  In the
fourth, it returns a vector of ones for the last index.  The
current octave-forge code gives an error for the second and fourth
cases and returns i, j, and k indices in a matrix for the first case.

jwe



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