The trailing space (instead of '0') in the third line of the printout of z, the fact that the decimal points are not aligned in the columns, and the left- justification of the column labels are hints that z is not a matrix of numbers, but just prints something like one. *> z* * [,1] [,2] [,3] [,4] [,5] * *[1,] 4.538 9.169 23.518 32.794 39.322* *[2,] 5.013 13.104 33.282 42.202 45.474* *[3,] 5.296 17.728 36.989 43.89 46.57 * E.g., compare the printouts of the following: > pNumeric <- matrix((1:6)*5.125, 3, 2) > pCharacter <- noquote(matrix(as.character((1:6)*5.125), 3, 2)) > pNumeric [,1] [,2] [1,] 5.125 20.500 [2,] 10.250 25.625 [3,] 15.375 30.750 > pCharacter [,1] [,2] [1,] 5.125 20.5 [2,] 10.25 25.625 [3,] 15.375 30.75 This is why R-help encourages people to show datasets using the output of dput(), which shows more of the actual structure of the data. > dput(pNumeric) structure(c(5.125, 10.25, 15.375, 20.5, 25.625, 30.75), .Dim = c(3L, 2L)) > dput(pCharacter) structure(c("5.125", "10.25", "15.375", "20.5", "25.625", "30.75" ), .Dim = c(3L, 2L), class = "noquote")
persp() gives odd error messages when x, y, or z is not numeric; it does not just say that character data is not allowed. Try reentering your data and looking at the output of str(z), str(x), and str(y) to make sure they are all numeric and that z is a matrix. > str(pNumeric) num [1:3, 1:2] 5.12 10.25 15.38 20.5 25.62 ... > str(pCharacter) 'noquote' chr [1:3, 1:2] "5.125" "10.25" "15.375" "20.5" "25.625" "30.75" Bill Dunlap Spotfire, TIBCO Software wdunlap tibco.com > -----Original Message----- > From: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] On > Behalf Of John Benning > Sent: Saturday, November 19, 2011 12:20 PM > To: r-help@r-project.org > Subject: [R] persp() problem > > Hi, and thanks in advance for any assistance, > > I'm new to R and to this mailing list, and am having trouble with the * > persp()* function. I've got a matrix (z) of values for various combinations > of x and y, each of which is a set of (0, 5, 10, 15, 20). But when I try * > persp(x,y,z)*, I get an "*invalid z argument*" error, and when I try simply > *persp(z)*, R returns an "*invalid x argument*" error, along with warning > messages. It seems like a very simple problem, so excuse my ignorance, but > any help would be greatly appreciated. Below is the printout from the > console. > > Many thanks, > > john > -------------------------------------------------------- > > *> x* > *[1] 0 5 10 15 20* > * > * > *> y* > *[1] 0 5 10 15 20* > * > * > *> z* > * [,1] [,2] [,3] [,4] [,5] * > *[1,] 4.538 9.169 23.518 32.794 39.322* > *[2,] 5.013 13.104 33.282 42.202 45.474* > *[3,] 5.296 17.728 36.989 43.89 46.57 * > *[4,] 5.366 20.94 39.244 44.987 47.177* > *[5,] 5.642 23.396 40.842 45.489 47.126* > * > * > *> persp(x,y,z)* > *Error in persp.default(x, y, z) : invalid 'z' argument* > * > * > *> persp(z)* > *Error in persp.default(z) : invalid 'x' argument* > *In addition: Warning messages:* > *1: In min(x, na.rm = na.rm) :* > * no non-missing arguments to min; returning Inf* > *2: In max(x, na.rm = na.rm) :* > * no non-missing arguments to max; returning -Inf* > *3: In min(x, na.rm = na.rm) :* > * no non-missing arguments to min; returning Inf* > *4: In max(x, na.rm = na.rm) :* > * no non-missing arguments to max; returning -Inf* > *5: In min(x, na.rm = na.rm) :* > * no non-missing arguments to min; returning Inf* > *6: In max(x, na.rm = na.rm) :* > * no non-missing arguments to max; returning -Inf* > > [[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. ______________________________________________ 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.