Julia: scatter plot with different colors (using either ColorGradient or other continuous color encodings)

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Very simple question but I'm not very familiar with the way the ColorGradient type works so I thought I'd ask here.

Say I have some x, y data that I want to plot in the standard way with scatter(x,y) and I want to color the dots with their unique colors based on a color map determined by a color gradient (see code below):

using Plots
C(g::ColorGradient) = RGB[g[z] for z=LinRange(0,1,30)]
g = :inferno

(source: https://github.com/JuliaPlots/ExamplePlots.jl/blob/master/notebooks/cgrad.ipynb)

How would I set up my color gradient object and then use it to map each of my (x,y) pairs to a different one of the colors in the color gradient, using the scatter() function?

My guess is something like:

x, y = (rand(10), rand(10))
using Plots
C(g::ColorGradient) = RGB[g[z] for z=LinRange(0,1,10)]
g = :blue

scatter(x,y,c=cgrad(g)|> C)

I just tried that and it works, but I don't really get why...what is with this |> C notation??

scatter-plot julia color-scheme plot colors
1 Answers

The shortest way to get the plot is:

using Plots, Colors
scatter(x,y,c=colormap("Blues",10))

Another colormap worth mentioning is to have very different colors of points:

scatter(x,y,c=distinguishable_colors(10))

The |> operator is just passing an argument to a function so you can write either f(x) or x |> f. Consider the example below:

julia> f(a,b=5) = a+b;

julia> 7 |> f
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