Please help me how to label curves like this

Question

Please tell me how to label curves like this:

any figure is fine, I just want to label the line as this example. — HANG YU, Oct 05 '23 at 12:21
When I search for "label curves mathematica" using Google, this link is the second one that pops up. Scroll down and see if adapting any of this will work. — march, Oct 05 '23 at 15:51
Please post at least one example with Mathematica code. I think you want the label just in the middle of the curves,and such circle-number labels will clip the curves. Maybe like this https://mathematica.stackexchange.com/questions/252802/imposing-breaks-in-contours-in-a-contourplot-without-rasterization — cvgmt, Oct 05 '23 at 23:50
see also How to place labels of many curves in good positions? — kglr, Oct 06 '23 at 07:37

score 4 · Answer 1 · answered Oct 06 '23 at 05:07

It starts with a curve by ParametricPlot, a RegionPlot and a Graphics list of objects bound together in a Show statemenent, e.g.

Show[{ParametricPlot[{t^2, 1/2 t + 1/4 t^4 Boole[t < 0]}, {t, -1, 1}],
   RegionPlot[   y > 0 && y > Sqrt[x/4] || x < 0 && y > 0, {x, -1, 1},
    {y, -1, 1}, PlotStyle -> {HatchFilling[]}],
     Graphics[{{Thickness[0.01], Line[{{-1, 0}, {0, 0}}]}, 
        {Thickness[0.01],Line[{{0, -1}, {0, 0}}]},
        {Style[Text["no effect", {-1/2, 1/2}], Bold, 16, Background ->
           White]},
         {Arrow[{{-1, -1}, {1, -1}}], 
           Style[Text["B", {1.1, -1}], Bold, 16],
         {Arrow[{{-1, -1}, {-1, 1}}], 
           Style[Text["K", {-1, 1.1}], Bold, 16]}}}],
         {Circle[{1/2, 1/3}, 0.06], Text["4", {1/2, 1/3}]} },
 PlotRange -> All, AxesOrigin -> {-1.2, -1.2},
    Ticks -> {{{-1, "S"/2}, {0, "S"}, {1/2, 8/5 "S"}}, {{-1, "S"}, {0, 
 "S/2"}, {1/2, "S"}}}]

Please help me how to label curves like this

1 Answers1