Hello
> -----Original Message----- > From: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] > On Behalf Of Katharina May > Sent: Monday, April 20, 2009 5:05 PM > To: r-help@r-project.org > Subject: [R] create objects in a loop and adding sqlQuery content to them > > Hi there, > > I've got a database or rather spreadsheet with several columns and rows. > For one column named sites I want to loop through all possible values > and retrieve > all data out of the database where site = x and write it into an > object named 'sitex_data'. > > Somehow I'm really missing something as I'm not able to create these > sitex_data objects with > the database values, neither using list nor assign... > > Here some code snipplets: > >library (RODBC) > >channel <- odbcConnectExcel2007 ("biomass_data.xlsx") > >site_data <- sqlQuery(channel, "select site_no from [biomass_data > $] group by site_no") > > #Here the values I want to loop through > >str(site_data) > 'data.frame': 44 obs. of 1 variable: > $ site_no: num 4 7 9 10 15 16 17 18 19 20 ... There's only 44 of them - can you show the whole thing? e.g. >site_data Also check the class of site_data$site_no It might be of class character or factor and not just numeric as it might initially appear. > > #Here my first try [error message on the line within the loop, saying > something like: > # 'recursive indexing on level 2 failed'] > sites_object_list <- vector("list",99) If there's a site number larger than 99 this will be problematic. > for(i in site_data) { > sites_object_list[[i]] <- sqlQuery(channel, paste("select * from > [biomass_data$] where site_no = ",i,sep="")) > } > > #Here my second try [error message on the line within the loop, > saying something like: > # 'only the first element will be used as variable name'] > for(i in site_data) { > assign(paste("site",i,"_data",sep=""), sqlQuery(channel, > paste("select * from [biomass_data$] where site_no = ",i,sep=""))) > > } I'm guessing one of the site numbers is not just a simple integer but has two numbers with a space or something in it. > > I would be very, very glad if anybody sends me a clue about this, as > I'm a obviuos Newbie using > R... > > Thanks, > > Katharina > > ______________________________________________ > 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. Steven McKinney, Ph.D. Statistician Molecular Oncology and Breast Cancer Program British Columbia Cancer Research Centre email: smckin...@bccrc.ca tel: 604-675-8000 x7561 BCCRC Molecular Oncology 675 West 10th Ave, Floor 4 Vancouver B.C. V5Z 1L3 Canada ______________________________________________ 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.