Warning messages in Splancs package :: no non-missing arguments to min; returning Inf
Dear Barry, I am new to R and I am sorry for the sens information. I am using R 2.8.1 for Windows. Does the error come from the kernel2d function, or from the image function? -- It comes from the kernel2d function. Does it do that for any data points? -- Not yet tried with other data, only two mentioned Shapefiles. They are correctly structured. Have you read the help for kernel2d? Have you tried the example in the help(kernel2d) text? -- I will look into it, thanks! Have you ever had it work? -- No, tries on two separate installations. Thanks for the solution, I will test it right away. Dejan On Mon, Mar 30, 2009 at 09:43, Barry Rowlingson
<b.rowlingson at lancaster.ac.uk> wrote:
On Mon, Mar 30, 2009 at 7:12 AM, D <eloquence2 at gmail.com> wrote:
Hi, I would need some help with the splans package in R. I am using a Shapefile (downloadable at) http://rapidshare.com/files/215206891/Redlands_Crime.zip and the following execution code setwd("C:\\Documents and Settings\\Dejan\\Desktop\\GIS\\assignment6\\DataSet_Redlands_Crime\\Redlands_Crime") library(foreign) library(splancs) auto_xy<-read.dbf("Auto_theft_98.dbf") rob_xy<-read.dbf("Robbery_98.dbf") auto.spp<-as.points(auto_xy$x/1000, auto_xy$y/1000) rob.spp<-as.points(rob_xy$x/1000, rob_xy$y/1000) image(kernel2d(auto.spp, bbox(auto.spp), h0=4, nx=100, ny=100), col=terrain.colors(10)) pointmap(auto.spp, col="red", add=TRUE) I would need to analyze the relationship betweeb the two Shapefiles, but I am receiving the following warning message and a blank output Xrange is ?1827.026 6796.202 Yrange is ?1853.896 6832.343 Doing quartic kernel Warning messages: 1: In min(x) : no non-missing arguments to min; returning Inf 2: In max(x) : no non-missing arguments to max; returning -Inf Can someone help me with what am I doing wrong in the execution code? I am getting a blank graph.
Well, do some investigation. Does the error come from the kernel2d function, or from the image function? Does it do that for any data points? Have you read the help for kernel2d? Have you tried the example in the help(kernel2d) text? Have you ever had it work? What version of R are you using and so on. Please read the posting guide. ?The manual for kernel2d says that the second argument has to be "A splancs polygon data set". But you've given it bbox(auto.spp). But bbox returns a matrix which is the wrong structure - the columns are min and max and the rows are X and Y. Plus it only has the corner points, not all four points of the box which splancs says it needs. There's also a clue in your output: ?Xrange is ?1827.026 6796.202 ?Yrange is ?1853.896 6832.343 ?- but if you plot the points (which you should always do, to make sure you've read them in properly) you should see that the X range should be 6796 to 6832 and the Y range should be 1827 to 1853. ?Solution: use the splancs bboxx() function that converts an sp-style bounding box to a splancs-style bounding box: ?k = kernel2d(auto.spp, bboxx(bbox(auto.spp)), h0=4, nx=100, ny=100) ?image(k) ?Barry