[R] running custom functions in Snow clusters

[Michael Gormley]

When running a function in parallel using for example the clusterCall 
function in Snow is it possible to call other user-written functions from 
each cluster?  I get an error when I try to do this.  I tried to source the 
function on each cluster using the clusterEvalQ function but this doesn't 
seem to work.  This is more of an aesthetic problem than an actual one as 
obviously I can write a group of functions as one function and call this 
with clusterCall.

Thanks,
Mike Gormley
Drexel University