Thank you Duncan (additional comments below), >-----Original Message----- >From: Duncan Murdoch [mailto:[EMAIL PROTECTED] >Sent: December 20, 2007 02:36 PM >To: Thompson, David (MNR) >Cc: r-help@r-project.org >Subject: Re: [R] Available environment variables > >On 20/12/2007 2:13 PM, Thompson, David (MNR) wrote: >> Hello, >> >> I am trying to set my environment to streamline the downloading / >> updating of packages. I have been through R-intro.html (10.8 >> Customizing-the-environment), R-FAQ (5.2 How can add-on packages be >> installed?), rw-FAQ, and help pages for Sys.setenv {base}, >> download.packages {utils}, etc.,. >> >> I am looking for something similar to the download.packages destdir >> argument on a global environment level, e.g., destdir <- 'C:/Program >> Files/_dave/stats/R/library/_download' in Rprofile.site. Any >> suggestions? > >You could create your own function: > >download.packages <- function(pkgs, destdir='C:/Program >Files/_dave/stats/R/library/_download', ...) > utils::download.packages(pkgs, destdir, ...) > >> Also, in a more general context, is there a way of listing all available >> (or common, or default, or standard, . . .) environment variables? > >Sys.getenv() will return a list of the ones that are currently defined. > >> I would like to know if there is an existing convention for any arbitrary >> process that I may try to do without reinventing the wheel. This same >> question could apply to options() other than those included with a >> standard installation. > >I don't know what you mean about an "arbitrary process". > >For options(), you could save the names that you consider standard (e.g. >by starting an empty session and entering standardoptions <- >names(options()), then at a later time do > >newoptions <- names(options()) >newoptions[ !(newoptions %in% standardoptions) ] > >There's no easy way to know the options that would mean something in the >current context but are not currently defined. >Duncan Murdoch
Creating a local copy of the function with alternate argument defaults works perfectly. I have done that in the past, don't know why I didn't think of it this time. Thank you. Saving initial- and post-session options (or their names) also nicely addresses part of my concern. Thank you. I am familiar with Sys.getenv() and was asking about potential environment variables that are NOT currently defined. However, while trying to rephrase my question, having reread the Startup {base} help and related documentation, could not clearly refine the issue in my own mind so, I am now content with the situation. I think that I may be confusing the intended use of environment files and profile files as noted in the details section of the Startup {base} documentation. Part of my concern is to find a way of safeguarding against my own errors and typos that may 'break the system' or having something installed later (the "arbitrary process" part) breaking my current setup. Also, I may be thinking of the startup process as something 'different' from the interactive R session processing, which I am beginning to see it is not. Thanks again, DaveT. ************************************* Silviculture Data Analyst Ontario Forest Research Institute Ontario Ministry of Natural Resources [EMAIL PROTECTED] http://ofri.mnr.gov.on.ca ______________________________________________ R-help@r-project.org 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.