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From: ps@fps.com (Patricia Shanahan)
Newsgroups: comp.lang.c
Subject: Re: Passing 2-D Arrays of unknown size ?
Message-ID: <5464@celit.fps.com>
Date: 20 Dec 89 22:51:57 GMT
References: <3180@uceng.UC.EDU>
Sender: daemon@fps.com
Reply-To: ps@fps.com (Patricia Shanahan)
Organization: FPS Computing Inc., San Diego CA
Lines: 28

I have sometimes used a macro to represent an array, especially when mixing
Fortran and C. 

#define Array(i,j) array[(i)*cols+(j)]

   for(i ...)
       for(j ...)
           some_operation(Array(i,j));

With more complicated macros, it is possible to handle non-zero base arrays.

#define Array(i,j) array[((i)-istart)*cols+(j)-jstart]

And of course column-major rather than row-major:

#define Array(i,j) array[((j)-jstart)*rows+(i)-istart]

And strides:

#define Array(i,j) array[((i)-istart)*cols*istride+((j)-jstart)*jstride]


In all cases the reference looks like Array(i,j).
--
	Patricia Shanahan
	ps@fps.com
        uucp : {decvax!ucbvax || ihnp4 || philabs}!ucsd!celerity!ps
	phone: (619) 271-9940