Frank -- Perhaps what you want to do is summarize <- function(lst) { lapply(lst, function(elt) { if (elt$status=="ok") elt$value else NA }) }
summarize(parLapply(tasks, function(elt) { # fancy calculation, then list(status="ok", value=...) })) i.e., return status along with value from the nodes, and 'post-process' the result. Perhaps status is set by capture.output on the node. Maybe you're hoping to change how later tasks are evaluated based on results of earlier tasks; but this makes the lapply sequential rather than parallel. Martin "Frank Preiswerk" <[EMAIL PROTECTED]> writes: > I am slightly confused by the way the standard output is redirected in a R > snow cluster environment. > I am using parLapply from the snow package to execute a function on my > MPI/LAM cluster. How can I redirect standard output (produced using "cat") > from this function back to the terminal where I invoked it? I intend to > transmit some status information in advance to the final result of the > function. I investigated the chain of functions called by parLapply and it > seems that snow is designed to just retrieve the final result of the > computation. > > Thanks in advance for any hints, > Frank Preiswerk > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help@stat.math.ethz.ch mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. -- Martin Morgan Bioconductor / Computational Biology http://bioconductor.org ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.