Add simpleunicodehistogram

from JuliaCI/BenchmarkTools.jl#180 (comment)

Co-authored-by: C. Brenhin Keller <[email protected]>

Author: ericphanson

src/plot_hist.jl

@@ -0,0 +1,35 @@
+function simpleunicodehistogram(x::AbstractArray; nbins::Integer=10, plotwidth::Integer=30, showcounts::Bool=true, xlabel="", ylabel="")
+    # Find bounds, round them nicely
+    l, u = extrema(x)
+    digitsneeded = ceil(Int, -log10(u-l))+1
+    l = floor(l, digits=digitsneeded)
+    u = ceil(u, digits=digitsneeded)
+
+    # Fill histogram
+    dx = (u - l) / nbins
+    histcounts = fill(0, nbins)
+    @inbounds for i ∈ 1:length(x)
+        index = ceil(Int, (x[i] - l) / dx)
+        if 1 <= index <= nbins
+            histcounts[index] += 1
+        end
+    end
+    binedges = range(l,u,length=nbins+1)
+
+    # Print the histogram
+    blocks = [" ","▏","▎","▍","▌","▋","▊","▉","█","█"]
+    scale = plotwidth/maximum(histcounts)
+    lowerlabels = string.(round.(binedges[1:end-1], digits=digitsneeded+ceil(Int,log10(nbins)-1)))
+    upperlabels = string.(round.(binedges[2:end], digits=digitsneeded+ceil(Int,log10(nbins)-1)))
+    longestlower = maximum(length.(lowerlabels))
+    longestupper = maximum(length.(upperlabels))
+    println(ylabel*"\n")
+    for i=1:nbins
+        nblocks = histcounts[i] * scale
+        blockstring = repeat("█", floor(Int, nblocks)) * blocks[ceil(Int,(nblocks - floor(nblocks))*8)+1]
+        println(" (" * lowerlabels[i] * " "^(longestlower - length(lowerlabels[i])) *
+                " - " * upperlabels[i] * " "^(longestupper - length(upperlabels[i])) *
+                    "]  " * blockstring * (showcounts ? " $(histcounts[i])" : ""))
+    end
+    println("\n" * " "^max(plotwidth÷2 + 6 - length(xlabel)÷2, 0) * xlabel)
+end