On Thu, Jul 3, 2008 at 5:09 PM, Ted <[EMAIL PROTECTED]> wrote: > While I am not a novice when it comes to statistics, this will be the first > time I have used R, apart from some intial play. I have normally written my > own code for statistical analysis in C++ or fortran, for a number of reasons > (in part contingent on what the boss was willing to pay for), and having been > programming for a long time, there is no need to spare me the programming > details. Just give me an url for a document that explains how to do what I > want to do, if there is one. > > What I want to do is extract time series data from a database(say, PostgreSQL > or MySQL - I routinely use both), analyse it, and put a selection of the > statistical results into specific tables.
For postgres see: https://stat.ethz.ch/pipermail/r-sig-db/2008q3/000458.html For MySQL try the RMySQL R package or you can use the RODBC R interface. R also has JDBC via the RJDBC R package. > > For example, suppose I have daily values for several variates. One thing I > might try is to fit a cubic spline to the data, use the spline to obtain an > estimate of rate of change and acceleration, and then see if some nonlinear > function of the variates can account for a significant percentage of the > variation in rate of change and acceleration, perhaps after orthogonalization > if there happens to be problems with multicollinearity. ?spline > > Since the data comes in regularly (daily in some cases, weekly in others), I'd > want to rerun the whole process at the same interval, without prior analyses > messing up a current analysis. > > I know of plr, for PostgreSQL, but haven't figured out how to use it yet. > > Is this something I can orchestrate using Perl to tie things together, either > using plr or not? If I can use perl for this, a sample perl script showing > how to use perl to get data into R and to retrieve statistical output from R > into Perl variables would be priceless. What I have read in the preliminary > documentation suggests I can, but it is short on detail and directions on > where to go next. I'd like to be able to put the master script for this sort > of thing into a scheduled task if possible. To run an external perl program from R, from within R try: ?system and ?shell or to run an R job from perl see ?BATCH To directly interface with perl: http://www.omegahat.org/RSPerl/ read.xls and xls2csv in the R gdata package use a perl program to read an Excel spreadsheet into R (although there are other methods that R has that do not depend on perl inlcuding COM and RODBC interfaces). That being said there is a good chance that you don't really need perl or if you do that you are doing something wrong. R itself has regular expressions and substantial string handling capability as well as many database and other interfaces. I personally used to use perl (prior to using R) but I virtually never use perl any more now that I have R. Issuing, from within R, RSiteSearch("...") can locate info on various R topics. ______________________________________________ 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.
