17 Jun
2001
17 Jun
'01
7:52 p.m.
On Sat, 16 Jun 2001, Maurice Lombardi wrote:
I have only the following experience with large arrays on gpc/djgpp (DOS): There is a 50% - 100% variation in execution times due to memory cache considerations (this cache is presumably the "level 2" 256 or 512 kB cache of the Pentiums). Matrices are stored in pascal row-wise (same for C but the opposite is true for fortran). If you access elements row after row you minimize cache breaks. In a
So how have you stored and accessed your NxM elements ?
The maximal size of my array is 2000x2000. Let's say I have:
X:array[1..N,1..M] od real;
I access it as:
for i:= 1 to N do for j:= 1 to M do bla-bla-bla.. x[i,j];
That's what you call row-wise acces or just the opposite?
miklos