Re: [UUG/MLUG] perl and y2k

[Mike Miller <EMAIL:PROTECTED>]

On Wed, 5 Jan 2000, Tymm Twillman wrote:

> or perhaps Matlab is broken too, or I'm reading things wrong.  But I
> usually trust C on this stuff.
> 
> http://www.ind2.polymtl.ca/matlab/techdoc/ref/mod.html (matlab
> documentation for mod)
> 
> it claims modulus is the *signed* remainder after division.


OK, but if you test this in MATLAB, you get the same result as in perl:


# mod(-98,100)

ans =

     2


And MATLAB documentation says:

M = mod(X,Y) returns the remainder X - Y.*floor(X./Y) for nonzero Y, and
returns X otherwise.

Which does the *same* thing as perl unless Y is zero, in which case perl
returns "Illegal modulus zero" and MATLAB returns X.

So it looks like perl and MATLAB are OK, but C and awk give wrong answers.  
This is what Jon and Steve said originally and I agree with them.

Regards,

Mike

-- 
Michael B. Miller
University of Missouri--Columbia
http://taxa.psyc.missouri.edu/~mbmiller/