Re: Data Help

*To*: mathgroup at yoda.ncsa.uiuc.edu*Subject*: Re: Data Help*From*: "Charles W. Fletcher" <cwf at lakisis.umd.edu>*Date*: Tue, 12 Feb 91 11:13:37 EST

I assume that you are using something like Plot[F[x],{x,a,b}] and you want to obtain the associated data (ascii) file of x-y values that were plotted. These data are in a list in the graphics. You may see it by using FullForm[Plot[...]] To get at the list you need to find it position and use the double bracket [[ ]] to separate it (See docs on lists of lists and on expressions.) Thus if u = Plot[F[x]...] then (if I remember correctly) u[[1,1,1,1,1]] is the list of data. This varies from plot type to plot type, so you may need to play around. For example, if u = Plot3D[...] then u[[1]] is the list of data. If you have problems, contact me and I'll pull out some of my old notebooks were I did this. One other thing, I talked to one of the WRI people and he (Kevin McIssac) noted the following. Due to the algorithm M. uses to plot the data values (ie, the x-values) may NOT (ie, are most likely not) evenly spaced. If this is what you want, okay. If not, you should use Table[] to generate the data. Good luck, Charlie