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From: willing@pantheon.seas.ucla.edu (Scott Willingham)
Newsgroups: comp.lang.c
Subject: Re: Column-wise data storage for matrices in C, any advantage(s)?
Keywords: store data in rows/columns, memory traffic, gaxpy rich
Message-ID: <1748@lee.SEAS.UCLA.EDU>
Date: 2 Feb 91 03:03:58 GMT
References: <1991Feb1.214342.4982@portia.Stanford.EDU>
Sender: news@SEAS.UCLA.EDU
Distribution: na
Organization: University of California at Los Angeles, EE dept.
Lines: 16

In article <1991Feb1.214342.4982@portia.Stanford.EDU> fangchin@elaine46.stanford.edu (Chin Fang) writes:
>...
>Now, note that this algorithm requires most rapid changes in indixing occuring
>in COLUMNS, not rows!
>
>I believe in default C design, data is stored in rows (discussed in K&R II)
>instead in columns.  It is almost very common these days people use 
>array of pointers to array as a way to simulate 2d matrices so that 
...

It seems to me that this is just a matter of syntax.  Whether you assign
the first or second _index_ of a C array to correspond to a matrix row
or column is arbitrary.  You just must be consistent in your usage
throughout the algorithm.

-- Scott D. Willingham