When you read the data into a data frame via read.csv, the character strings in the first row of the data file, which you've indicated is to be interpreted as a header, are used for column names; in the process, blanks are converted to periods, since nonstandard names including blanks are more difficult to deal with; names(df[13]) just returns the name of column 13 in the data frame. You could use the gsub function to recover the blanks -- something like gsub("\\."," ", names(df[2])). Alternatively, you could specify the argument check.names=FALSE to read.csv to avoid substituting periods for blanks in the first place, but this probably isn't a good idea. See ?read.csv for details.
I hope that this helps,
John
At 09:33 AM 2/11/2003 -0700, Tom Arnold wrote:
Basic question: when I use names() to extract the name of a dataframe element, why does it have "." instead of " " between words?Context: I'm importing a CSV file of survey results for analysis. I read them like this: df <- read.csv("surveydata.csv",nrows=40,header=TRUE, na.string=c("N/A",""),comment.char="",strip.white=TRUE) To do a summary of the responses to a question, I can now do something like this: table(df[13]) 1 2 3 4 13 13 4 2 and can then do a barplot with: barplot(table(df[13]))) Which is fine. But since the first row of my data file includes the questions themselves, I want to use those questions as chart titles, like this: barplot(table(df[13]),main=names(df[13])) This gives an unexpected result: the title has a "." where every space should be between words, like this: "How.many.cats.do.you.own" I can't figure out why, or how to get spaces instead of "." to show up. I've tried using gsub but without success, to substitute " " for "." I'm think I'm confused about something fundamental here, and hope someone has the patience to enlighten me. I confess to a being a bit vague in my understanding of R's handling of arrays, dataframes, and vectors. My background is in C programming and I keep looking for a "string"... Thank you very much. Please reply or copy me directly if you respond. Tom Arnold Managing Partner, Summit Media Partners LLC Visit our web site at http://www.summitmediapartners.com ______________________________________________ [EMAIL PROTECTED] mailing list http://www.stat.math.ethz.ch/mailman/listinfo/r-help
----------------------------------------------------- John Fox Department of Sociology McMaster University Hamilton, Ontario, Canada L8S 4M4 email: [EMAIL PROTECTED] phone: 905-525-9140x23604 web: www.socsci.mcmaster.ca/jfox ----------------------------------------------------- ______________________________________________ [EMAIL PROTECTED] mailing list http://www.stat.math.ethz.ch/mailman/listinfo/r-help
