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From: luj@delta.ecn.purdue.edu (Jun Lu)
Newsgroups: comp.lang.c
Subject: How to pass arbitrary 2-d array argument ?
Message-ID: <1991Jan6.044056.23028@noose.ecn.purdue.edu>
Date: 6 Jan 91 04:40:56 GMT
Sender: news@noose.ecn.purdue.edu (USENET news)
Followup-To: comp.lang.c
Organization: Purdue University School of Aeronautics and Astronautics
Lines: 45

It would be nice if I can have a "subroutine" which takes arbitrary matrices as
arguments and performs some operations on them. The dimensions of the 2-d
array are not known a priori.  In other words, how do you add two
matrices together portably in C ? ( see following scenario descriptions )

main()
{
     double m1[4][2], m2[4][2], m[4][2];
     double a[5][5], b[5][5], c[5][5];

     /* init m1, m2 ... */


     madd(m1, m2, m, 4, 2);
     madd(a, b, c, 5, 5);

     /* ... */

}

madd(a, b, c, m, n)
 /* args --- how ???(Note n is not known at compile time, but we assume that
    the type of the 2-d array elements are known, i.e. double */
{
    /*
     * some work --- how ????
     */

     for (i = 0; i < m; i++)		/* fucntionality of madd() */
	for (j = 0; j < n; j++)
	    c[i][j] = a[i][j] + b[i][j];

}

No calling Fortran from C please. 

Any suggestions/comments/pointers are welcome. I'm looking forward to
hearing from you ...

Thanks,
--
-- Jun Lu                          Internet:luj@ecn.purdue.edu          --
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