Hi Mark, X = 1 assings the number 1 to X whereas
X == 1 test if X is equal to 1. I suspect you want to do this :-) Here is an example: # R code X = 1 X # [1] 1 X == 1 # [1] TRUE HTH, Jorge On Tue, Jul 7, 2009 at 3:06 PM, Mark Knecht <markkne...@gmail.com> wrote: > Hi, > I am apparently not understanding some nuance about either the use > of subset or more likely my ability to test for a numerical match > using '='. Which is it? Thanks in advance. > > I've read a data file, reshaped it and then created MyResults by > keeping only lines where the value column is greater than 0. So far so > good. The data in MyResults looks good to me by eye. > > The problem comes in when I try to further subset MyResults into > two files, one with PosType=1 and the other with PosType=-1. Looking > at the dimension of the results there's no change. It didn't work > which is verified by eye. However if I test for PosType=1 by actually > testing for PosType>0 then it does work. > > Is this the general case in R that if I've read data that was > written into a csv file as 1 - it is 1 if I look into the file with a > text editor - that I cannot test for that? Or is some case where I > need to use maybe as.numeric or something else first to ensure R sees > the number the way I'm thinking about the number? > > Cheers, > Mark > > > dim(X) > [1] 25 425 > > > > ReShapeX <- melt(X, id = c("Trade", "PosType", "EnDate", "EnTime", > "ExDate", "ExTime", "PL_Pos", "Costs", "Save2")) > > > > dim(ReShapeX) > [1] 10400 11 > > > > MyResults <- subset(ReShapeX, value > 0) > > > > dim(MyResults) > [1] 1105 11 > > > > MyResults.GroupA <- subset(MyResults, PosType = 1) > > > > dim(MyResults.GroupA) > [1] 1105 11 > > > > MyResults.GroupB <- subset(MyResults, PosType = -1) > > > > dim(MyResults.GroupB) > [1] 1105 11 > > > > MyResults.GroupA <- subset(MyResults, PosType > 0) > > > > dim(MyResults.GroupA) > [1] 432 11 > > > > MyResults.GroupB <- subset(MyResults, PosType < 0) > > > > dim(MyResults.GroupB) > [1] 673 11 > > > > ______________________________________________ > 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. > [[alternative HTML version deleted]] ______________________________________________ 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.