Date:	Tue, 13 Jul 1993 18:59:13 -0600
From:	jweiss AT silver DOT sdsmt DOT edu (John M. Weiss)
To:	djgpp AT sun DOT soe DOT clarkson DOT edu

Mat Hostetter <iclone!mjhostet AT cs DOT unm DOT edu> wrote:

There is no reason to use an array of pointers to the beginning of  
lines if you use the proper C types. I believe this does what you want:

#define NROWS 512
#define NCOLS 512

typedef int row[NCOLS];
...
  row *my_matrix = (row *) malloc (sizeof (row) * NROWS);
  my_matrix[123][456] = 7;
...

------------------------------------------------------------------

This is a good technique to be aware of, but not a general solution to
dynamically allocating 2-D arrays.  The problem is that you may not
know NCOLS at compile time.  What happens when the image size is, say,
800x600 instead of 512x512?  You have to recompile with a new #define.

See ALLOC2D.ZIP for a more general solution.

				- JW

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