RE: graph
- To: mathgroup at smc.vnet.net
- Subject: [mg39665] RE: graph
- From: "David Park" <djmp at earthlink.net>
- Date: Sat, 1 Mar 2003 02:47:18 -0500 (EST)
- Sender: owner-wri-mathgroup at wolfram.com
Rodolphe, Load Needs["NumericalMath`SplineFit`"] Use this statement... Show[Graphics[{}], Frame -> True, PlotRange -> {{-10, 10}, {-10, 10}}, GridLines -> Automatic, ImageSize -> 500]; except substitute the PlotRange that you want for your function. Then click off the points for your curve and copy them. For example, here are some points I clicked off, copied and pasted into my notebook. pts = {{-6.59751, -3.49975}, {-4.02183, -1.27227}, {-1.22411, 1.38633}, {1.17394, 1.45819}, {3.572, -1.05671}, {6.14768, -3.71532}, {8.45691, -6.37392}}; Then I created a spline function. spline = SplineFit[pts, Cubic] SplineFunction["Cubic", "{0., 6.}", <>] This plots the resulting curve. ParametricPlot[spline[u], {u, 0, 6}, Compiled -> False, Frame -> True, PlotRange -> {{-10, 10}, {-10, 10}}, GridLines -> Automatic, ImageSize -> 500]; Or perhaps you don't want a spline function, but just want to connect the points by straight lines. Then Show[Graphics[ {AbsolutePointSize[4], Point /@ pts, Line[pts]}], Frame -> True, PlotRange -> {{-10, 10}, {-10, 10}}, GridLines -> Automatic, ImageSize -> 500]; The DrawGraphics package, at my web site, has a command DrawIndexedPoints that plots a set of clicked off points and numbers them. You can then easily edit the points by adding, replacing or changing existing points. David Park djmp at earthlink.net http://home.earthlink.net/~djmp/ From: Rodolphe [mailto:rodolphe_lampe at yahoo.fr] To: mathgroup at smc.vnet.net I want to put a graph but without function since I must trace myself the function so I want the graduations but no functions ... thx