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Foreach help!

3 messages · Cloneberry, R. Michael Weylandt

Cloneberry
# 
Hi,
just during these vacation days, I'm trying to approach with multicore
package
and I have some troubles with foreach.

ex.
foreach(.combine=c, ii=1:200, jj=1:500) %dopar% makefunction[ii,jj]

Command seem to work but if I see ii and jj value at the and of cycle, they
are both 200
instead than ii=200 and jj=500.

Why??
Can someone help me?

Thank you in advance.

Max




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R. Michael Weylandt
# 
I believe that foreach() only goes along the "shorter" of the
iteration vectors.

E.g.,

foreach(.combine = c, i = 1:10, j = 1:15) %do% print(i + j)

stops when i == 10 (and j = 10 as well). To make it more explicit

foreach(.combine = c, i = 1:10, j = 11:25) %do% print(i + j)

stops when j = 20 because you run out of "i"

foreach does not seem designed for exhaustive search -- you might need
expand.grid() or some such if you want the cartesian product of ii and
jj.

Best,
Michael
On Wed, Aug 1, 2012 at 9:09 AM, Cloneberry <cloneberry at gmail.com> wrote: