BarLegend display Pi

Question

BarLegend["LakeColors", {0.2, 0.4, 0.6, 0.8}]

I want to display Pi in the BarLegend. I can do similar thing in FrameTicks like this

FrameTicks->{0, {Pi/4, "\[Pi]/4"}, {Pi/2,"\[Pi]/2"}, {3 Pi/4, "3\[Pi]/4"}, {Pi, "\[Pi]"}};

But it doesn't work in BarLegend. How to solve it?

Hmm.. Unfortunately the documentation doesn't make it look immediately possible with a standard piece of functionality, but maybe it's possible with some finnicking. — ktm, Oct 28 '16 at 02:51

score 7 · Answer 1 · answered Oct 28 '16 at 06:04

7

One can use the undocumented option Ticks instead of FrameTicks.

BarLegend[{"LakeColors", {0, 2}}, 
 Ticks -> {0, {Pi/4, "π/4"}, {Pi/2, "π/2"}, {3 Pi/4, "3π/4"}, {Pi, "π"}}]

answered Oct 28 '16 at 06:04

Karsten7

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score 3 · Answer 2 · answered Oct 28 '16 at 03:17

Write your own, for example:

dat = Table[{ColorData["LakeColors", n], 
    Rectangle[{0, n}, {.2, n + 1/3}]}, {n, 0, 1, 1/3}];
labels = Table[{GrayLevel[.5], Line[{{0, n*4/3}, {.3, n*4/3}}], Black,
     Inset[Rationalize[n]*Pi, {.4, n*4/3}]}, {n, 0, 1, .25}];
myLegend = Graphics[{dat, labels}, ImageSize -> 50];
Labeled[ContourPlot[Sin[x  y], {x, 0, \[Pi]}, {y, 0, \[Pi]}, 
  Contours -> 3, ColorFunction -> "LakeColors"], myLegend, Right]

I do concede this is not immediately as pretty as the default (you can adjust that though), and not nearly as easy, but it offers more customization. And if customizing your tick labels isn't possible (who knows) it may be a good option.

You can add any other graphics you'd like as well, i.e. more borders, more ticks, etc...

I hope someone comes along and provides a better solution, however!

BarLegend display Pi

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