Add ticks getter functions (#3435)

* Add ticks getter functions

* Add tick-getter functions for Plot objects

* Fix boiler-plate code in get_ticks

* Bump minor version + add tests

* Remove kwargs and add subplot test

* Add docstrings

* bump minor version

Project.toml

@@ -1,7 +1,7 @@
 name = "Plots"
 uuid = "91a5bcdd-55d7-5caf-9e0b-520d859cae80"
 author = ["Tom Breloff (@tbreloff)"]
-version = "1.12.0"
+version = "1.13.0"
 
 [deps]
 Base64 = "2a0f44e3-6c83-55bd-87e4-b1978d98bd5f"

src/axes.jl

@@ -235,6 +235,66 @@ function get_ticks(sp::Subplot, axis::Axis; update = true)
     return axis.plotattributes[:optimized_ticks]
 end
 
+# Ticks getter functions
+for l in (:x, :y, :z)
+    axis = string(l, "-axis")  # "x-axis"
+    ticks = string(l, "ticks") # "xticks"
+    f = Symbol(ticks)          # :xticks
+    @eval begin
+        """
+            $($f)(p::Plot)
+
+        returns a vector of the $($axis) ticks of the subplots of `p`.
+
+        Example use:
+
+        ```jldoctest
+        julia> p = plot(1:5, $($ticks)=[1,2])
+
+        julia> $($f)(p)
+        1-element Vector{Tuple{Vector{Float64}, Vector{String}}}:
+         ([1.0, 2.0], ["1", "2"])
+        ```
+
+        If `p` consists of a single subplot, you might want to grab
+        only the first element, via
+
+        ```jldoctest
+        julia> $($f)(p)[1]
+        ([1.0, 2.0], ["1", "2"])
+        ```
+
+        or you can call $($f) on the first (only) subplot of `p` via
+
+        ```jldoctest
+        julia> $($f)(p[1])
+        ([1.0, 2.0], ["1", "2"])
+        ```
+        """
+        $f(p::Plot) = get_ticks(p, $(Meta.quot(l)))
+        """
+            $($f)(sp::Subplot)
+
+        returns the $($axis) ticks of the subplot `sp`.
+
+        Note that the ticks are returned as tuples of values and labels:
+
+        ```jldoctest
+        julia> sp = plot(1:5, $($ticks)=[1,2]).subplots[1]
+        Subplot{1}
+
+        julia> $($f)(sp)
+        ([1.0, 2.0], ["1", "2"])
+        ```
+        """
+        $f(sp::Subplot) = get_ticks(sp, $(Meta.quot(l)))
+        export $f
+    end
+end
+# get_ticks from axis symbol :x, :y, or :z
+get_ticks(sp::Subplot, s::Symbol) = get_ticks(sp, sp[Symbol(s, :axis)])
+get_ticks(p::Plot, s::Symbol) = [get_ticks(sp, s) for sp in p.subplots]
+
 function get_ticks(ticks::Symbol, cvals::T, dvals, args...) where T
     if ticks === :none
         return T[], String[]

test/test_axes.jl

@@ -21,3 +21,13 @@ end # testset
     @test Plots.get_ticks(p2[1], p2[1][:xaxis])[2] == string.('C':3:'Z')
     @test Plots.get_ticks(p3[1], p3[1][:xaxis])[2] == string.('A':'Z')
 end
+
+@testset "Ticks getter functions" begin
+    ticks1 = ([1,2,3], ("a","b","c"))
+    ticks2 = ([4,5], ("e","f"))
+    p1 = plot(1:5, 1:5, 1:5, xticks=ticks1, yticks=ticks1, zticks=ticks1)
+    p2 = plot(1:5, 1:5, 1:5, xticks=ticks2, yticks=ticks2, zticks=ticks2)
+    p = plot(p1, p2)
+    @test xticks(p) == yticks(p) == zticks(p) == [ticks1, ticks2]
+    @test xticks(p[1]) == yticks(p[1]) == zticks(p[1]) == ticks1
+end