Re: plotting multidimensional arrays

*To*: mathgroup at smc.vnet.net*Subject*: [mg69605] Re: plotting multidimensional arrays*From*: mickey <micky at hotmail.com>*Date*: Sun, 17 Sep 2006 06:57:34 -0400 (EDT)*Organization*: Ohio State University*References*: <eegb31$js$1@smc.vnet.net>

David Annetts wrote: > Hi Mickey, > > >>I have a list of numbers, >>cc(1,2)=20 >>cc(1,3)=45 >> >>and so on. I would like to plot it as a 3 dimensional plot, >>with the index as x and y and the value as the z value but I >>am having trouble doing that. Here is what I was trying. I >>create the array first, >> >>cc=Table[0,{i,500},{j,500}]; > > > You are creating an 500 x 500 array filled with zeros. > > >>This works fine. Then I assign the values for the elements. >> >>cc[[1]][[2]]=20; > > > This will return the 2nd element in the first row. You mean cc[[1, 2]] = > 20; > > >>But here I get an error. > > > Yes. Look at Part[] in the online help. > > >>What am I doing wrong? > > > At the very least, assuming that you can write C(++) like code and expect it > to work .... > > You say you have a list of numbers. Where? On paper? In a file on your > disc? Assuming it's the latter, we can read them directly into Mathematica. > > idat = Import["c:/Tmpfiles/Surface.dat", "CSV"]; > idat = ToExpression[#] & /@ idat; > > And plot them as a surface (after loading the proper package) > > Needs["Graphics`"] > ListSurfacePlot3D[idat]; > > Or as discrete points ... > > rdat = Partition[Flatten@idat, 3]; > ScatterPlot3D[rdat]; > > It depends on how you read your data from the file on disc, and what exactly > you want to do with them. > > How about looking at the help for Import[] as well as ListPlot3D & > ListSurfacePlot3D. Try the examples. Look at the start of the sample data > to see the required format for the data. > > Regards, > > Dave. > Thanks to everyone who responded. It works fine now. -M