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I'm occasionally in a situation where I have to use Mathematica on the terminal. I'd like to visualize the solutions I get from NDSolve, but when I use Plot, Mathematica just shows -Graphics- instead of trying to plot anything. I decided to write my own function for this:

AsciiPlot[functionsl_, {t_, tmin_, tmax_}] := Module[ {buffer, pts, width, height, ymin, ymax, s, functions, function, allpts}, width = 77; height = 24; buffer = Table[" ", {height}, {width}]; If[Head[functionsl] === List, functions = functionsl, functions = {functionsl}];(*ensure functions is a list even if of length 1*) allpts = Table[{x, (functions[[j]]) /. t -> x} // N, {j, Length[functions]}, {x, tmin, tmax, (tmax - tmin)/width}]; (*Min and max of all y's across all functions to plot*) ymin = Min[allpts[[1 ;;, 1 ;;, 2]]]; ymax = Max[allpts[[1 ;;, 1 ;;, 2]]]; s = (ymax - ymin)/(tmax - tmin); For[i = 1, i <= Length[functions], i++, function = functions[[i]]; pts = allpts[[i]]; (*I think it is bad form to declare a function inside a module, but it needs the variables and it is a pain to pass them all as arguments*) set[point_, letter_] := ( buffer[[height - point[[2]] + 1, point[[1]]]] = letter;); PickLetter[slope_] := Piecewise[{{"-", -.65 s < slope < .65 s}, {"/", .65 s <= slope < 3.5 s}, {"|", 3.5 s <= slope}, {"\\", -3.5 s < slope <= -.65 s}, {"|", slope <= -3.5 s}}, "*"]; ScalePoint[p_] := Round[{(p[[1]] - tmin)*(width - 1)/(tmax - tmin) + 1, (p[[2]] - ymin)*(height - 1)/(ymax - ymin) + 1}]; Map[set[ScalePoint[#], PickLetter[D[function, t] /. t -> #[[1]]]] &, pts, 1];](*end for each function*) Map[Print[StringJoin[#]] &, buffer, 1];]

How can I extend this to plot axes as well? My strategy (forcing even one function to be a list) for plotting multiple functions to mimick the native Plot[]'s behavior seems pretty unintuitive. Is there a better way?

Also, I would have preferred a function that could work on a Raster object, which would allow me also to use things like ParametricPlot and even the 3D plots with no extra effort. I couldn't think of a way to get around needing the derivative short of trying to fit curves to the rasterized image and plotting those. Any tips?

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If you're stuck with the terminal, but have access to X11 and Java, then I suggest using JavaGraphics`, which allows you to display plots, but continue to work in the terminal. This was also answered here, but I learnt it from from Jens.

If you really want an ASCII plot, I suggest using the Terminal` package that gives you an ASCII plot:

<< Terminal` Plot[Sinc[x], {x, 0, 20}, PlotRange -> All]

enter image description here

It also works in the front end (although, I don't know why anyone would use it in the FE):

enter image description here

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  • $\begingroup$ Wow! I had no idea this existed. Unfortunately, I get Can't open display ":0.0" when I try it. I am connecting to a linux machine that is at runlevel 3 (no X11 or any graphical interface) using ssh. $\endgroup$ Commented Nov 1, 2012 at 3:19
  • $\begingroup$ @user141603 JavaGraphics won't work without X11, but if even Terminal (which doesn't require JavaGraphics) doesn't work for you, then I don't know... please try using only Terminal in a fresh kernel $\endgroup$ Commented Nov 1, 2012 at 3:24
  • $\begingroup$ I am running CentOS 6.3. I reboot, login at the "localhost login:" prompt, run "math", type "<<Terminal`" and get that error... Very odd. $\endgroup$ Commented Nov 2, 2012 at 3:34
  • $\begingroup$ @user141603 It doesn't work for me either... on runlevel 3 Mathematica even produces a segfault. $\endgroup$ Commented Nov 2, 2012 at 9:39
  • $\begingroup$ @sebhofer I've never gotten a segfault. Are you using CentOS? $\endgroup$ Commented Nov 6, 2012 at 2:12

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