Merge pull request #886 from daschw/ds-spy

Changed spy recipe and added spy example to tests (fix #883)

src/examples.jl

@@ -319,6 +319,15 @@ PlotExample("Animation with subplots",
     end)]
 ),
 
+PlotExample("Spy",
+    "For a matrix `mat` with unique nonzeros `spy(mat)` returns a colorless plot. If `mat` has various different nonzero values, a colorbar is added. The colorbar can be disabled with `legend = nothing`. As always, the marker shape and size can be changed with `spy(mat, markersize = 3, markershape = :star)`",
+    [:(begin
+    a = spdiagm((ones(50), ones(49), ones(49), ones(40), ones(40)),(0, 1, -1, 10, -10))
+    b = spdiagm((1:50, 1:49, 1:49, 1:40, 1:40),(0, 1, -1, 10, -10))
+    plot(spy(a, markershape = :dtriangle), spy(b), markersize = 3, title = ["Unique nonzeros" "Different nonzeros"])
+    end)]
+),
+
 ]
 
 # ---------------------------------------------------------------------------------

src/recipes.jl

@@ -976,6 +976,9 @@ end
     @assert length(g.args) == 1 && typeof(g.args[1]) <: AbstractMatrix
     seriestype := :spy
     mat = g.args[1]
+    if length(unique(mat[mat .!= 0])) < 2
+        legend --> nothing
+    end
     n,m = size(mat)
     Plots.SliceIt, 1:m, 1:n, Surface(mat)
 end
@@ -999,6 +1002,7 @@ end
     y := rs
     z := nothing
     seriestype := :scatter
+    grid --> false
     ()
 end