It may be educational to read the help pages of functions that you're using, namely ?I (or even ?AsIs) and ?as.vector. ?I says it simply prepend "AsIs" to the class attribute of the object. ?as.vector says it returns FALSE if the object has any attributes except names (which it does in this case: the class). Note that str() does tell you that it's `chr', or character. You can unclass() it to see what it actually is.
HTH, Andy > From: michael watson (IAH-C) > > > OK I'm definitely being a bit ignorant (so please accept my apologies) > of R and it's internal data storage. > > When I created the data.frame, I did use I() with this column - the > original data being a vector created simply with "vector()". > It's clear > now that I didn't realise exactly what this was doing (all I > wanted was > for it to NOT be converted to a factor). > > > str(submin[,display.gname]) > Class 'AsIs' chr [1:4622] "" "" "" "" ... > > is.array(submin[,display.gname]) > [1] FALSE > > class(submin[,display.gname]) > [1] "AsIs" > > But I am still confused; I program mainly in perl and java, and this > "thing" - it's not a vector, an array, a matrix or a data.frame - so > what is "it"? :-S > > Thanks > > Mick > > > -----Original Message----- > From: Liaw, Andy [mailto:[EMAIL PROTECTED] > Sent: 17 December 2004 15:55 > To: michael watson (IAH-C); [EMAIL PROTECTED] > Subject: RE: [R] If it's not a data.frame, matrix or vector, > what is it? > > > What does str(submin$display.gname) say? > > Andy > > > From: michael watson (IAH-C) > > > > Hi > > > > Forgive my ignorance. I am selecting a column of a > > data.frame using the > > column name, and I want to know what the resulting column > > "is". My data > > frame is called "submin" and the column name is held in a variable > > called "display.gname" Eg: > > > > > is.data.frame(submin) > > [1] TRUE > > > is.data.frame(submin[,display.gname]) > > [1] FALSE > > > is.matrix(submin[,display.gname]) > > [1] FALSE > > > is.vector(submin[,display.gname]) > > [1] FALSE > > > length(submin[,display.gname]) > > [1] 4622 > > > > So if it's not a data.frame, a matrix or a vector, what is "it"? > > > > Thanks (and sorry if this is in the FAQ) > > > > Mick > > > > ______________________________________________ > > [EMAIL PROTECTED] mailing list > > https://stat.ethz.ch/mailman/listinfo/r-help > > PLEASE do read the posting guide! > > http://www.R-project.org/posting-guide.html > > > > > > > -------------------------------------------------------------- > ---------- > ------ > Notice: This e-mail message, together with any attachment...{{dropped}} ______________________________________________ [EMAIL PROTECTED] mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
