[?] Reverse BarLegend colors?

Questions
1

I’ve made this BarLegend:

BarLegend[{"Rainbow", {15, 45}}, LegendLabel -> "P (m)", 
 LegendMarkerSize -> 200, LegendLayout -> "Row"]

Is there any way to reverse its colors?

Thank you in advance!

2

BarLegend[{{“Rainbow”, “Reverse”}, {15, 45}}, LegendLabel → “P (m)”,
LegendMarkerSize → 200, LegendLayout → “Row”]

3308plot.png

3

Thank you very much! It’s exactly what I wanted!

However, it doesn’t work with ColorData:

ColorData[{{"Rainbow", "Reverse"}, {15, 45}}]
(*ColorData::notent: {{Rainbow,Reverse},{15,45}} is not a known entity, class, or tag for ColorData. Use ColorData[] for a list of entities.*)
4

Not sure what you are trying to achieve. If you want to use a different gradient you can use any of the ones supported by ColorData.

ColorData["Gradients"]
(* {"AlpineColors", "Aquamarine", "ArmyColors", "AtlanticColors", 
"AuroraColors", "AvocadoColors", "BeachColors", "BlueGreenYellow", 
"BrassTones", "BrightBands", "BrownCyanTones", "CandyColors", 
"CherryTones", "CMYKColors", "CoffeeTones", "DarkBands", 
"DarkRainbow", "DarkTerrain", "DeepSeaColors", "FallColors", 
"FruitPunchColors", "FuchsiaTones", "GrayTones", "GrayYellowTones", 
"GreenBrownTerrain", "GreenPinkTones", "IslandColors", "LakeColors", 
"LightTemperatureMap", "LightTerrain", "MintColors", "NeonColors", 
"Pastel", "PearlColors", "PigeonTones", "PlumColors", "Rainbow", 
"RedBlueTones", "RedGreenSplit", "RoseColors", "RustTones", 
"SandyTerrain", "SiennaTones", "SolarColors", "SouthwestColors", 
"StarryNightColors", "SunsetColors", "TemperatureMap", 
"ThermometerColors", "ValentineTones", "WatermelonColors"} *)

e.g.

BarLegend[{{"TemperatureMap", "Reverse"}, {15, 45}}, 
 LegendLabel -> "P (m)", LegendMarkerSize -> 200, 
 LegendLayout -> "Row"]

4364plot.png

5

Yes, I think I haven’t explained myself very well…

I want to change also the colors accordingly into a ListDensityPlot. Here is an example:

plotz = ListDensityPlot[
   Table[Sin[x y], {x, 0, 3, 0.1}, {y, 0, 3, 0.1}], 
   DataRange -> {{0, 3}, {0, 3}}, PerformanceGoal -> "Quality", 
   ColorFunction -> ColorData[{"Rainbow", {-1, 1}}], 
   ColorFunctionScaling -> False, InterpolationOrder -> 1];
bl = Placed[
   BarLegend[{"Rainbow", {-1, 1}}, LegendMarkerSize -> 200, 
    LegendLayout -> "Row"], Above];
Legended[plotz, bl]

So I need to reverse both the BarLegend and the ColorFunction. The {-1,1} limits are important to be kept for comparison with other plot. However, the technique of Reverse works into BarLegend but not into ColorData.

Thanks again for useful comments!

6

Thanks for clarifying. Reversing the range passed to ColorData seems to work. Yes?

plotz = ListDensityPlot[
   Table[Sin[x y], {x, 0, 3, 0.1}, {y, 0, 3, 0.1}], 
   DataRange -> {{0, 3}, {0, 3}}, PerformanceGoal -> "Quality", 
   ColorFunction -> ColorData[{"Rainbow", {1, -1}}], 
   ColorFunctionScaling -> False, InterpolationOrder -> 1];
bl = Placed[BarLegend[{{"Rainbow", "Reverse"}, {-1, 1}}, 
    LegendMarkerSize -> 200, LegendLayout -> "Row"], Above];
Legended[plotz, bl]

3552plot.png
3552plot.png450×516 71.3 KB

7

It works!

Clever solution!

Thank you very much Rohit!