Merge pull request #59 from fremling/master

Allow latex support in Jupyter notebooks

Author: fremling

README.md

@@ -132,6 +132,10 @@ julia> P12 * [W"a" W"b" ; W`a+b` 2] == [ W"b" 2-W"b" ; W"a" W"b"]
 true
 ```
 
+## LateX printing in JuPyter Notebooks
+Printing in Juypter notebooks is by defaults done in latex.
+This can be turned off with the command `MathLink.set_texOutput(false)`
+
 ## Notes
 
 - Mathematica, Wolfram, MathLink are all trademarks of Wolfram Research.

src/display.jl

@@ -1,4 +1,4 @@
-const graphics = (W"Graphics", W"Graphics3D", W"Legended")
+const graphics = (W"Graphics",W"GeoGraphics", W"Graphics3D", W"Legended")
 
 Base.Multimedia.showable(::MIME"image/svg+xml", w::MathLink.WExpr) = in(w.head, graphics)
 Base.show(io::IO, ::MIME"image/svg+xml", w::MathLink.WExpr) = print(io, weval(W"ExportString"(w, "SVG")))
@@ -8,3 +8,89 @@ function Base.show(io::IO, ::MIME"image/png", w::MathLink.WExpr)
     x = weval(W"ExportByteArray"(w, "PNG"))
     write(io, x.args[1].args)
 end
+
+
+####If the flag for tex-output evaluation does not exist
+## create it and set it to true.
+if !@isdefined(MLtexOutput)
+    MLtexOutput=true
+end
+
+export set_texOutput
+function set_texOutput(x::Bool)
+    global MLtexOutput
+    MLtexOutput=x
+end
+
+export HasGraphicsHead, HasRecursiveGraphicsHead, W2Tex
+
+
+#### Code to produce LaTex strings
+W2Tex(x::WTypes) = weval(W`ToString@TeXForm[#]&`(x))
+
+#### Allow latex string to be shown when supported. Relevant for the jupyter notebook.
+
+HasRecursiveGraphicsHead(w::MathLink.WSymbol) = false
+function HasRecursiveGraphicsHead(w::MathLink.WExpr)
+    if HasGraphicsHead(w)
+        return true
+    end
+    for arg in w.args
+        if typeof(arg) == MathLink.WExpr
+            ##Only check for MathLink Expressions
+            if HasRecursiveGraphicsHead(arg)
+                return true
+            end
+        end
+    end
+    return false
+end
+
+function HeadsEndsWith(HeadString,Target)
+    ###Check if name ends with $Target
+    if length(HeadString) >= length(Target)  
+        return  HeadString[end-(length(Target)-1):end] == Target
+    end
+    return false
+end
+
+
+const graphics_heads = (W"Graphics", W"Graphics3D", W"Legended")
+
+###Check if an expression has a grapics head
+HasGraphicsHead(w::MathLink.WSymbol) = false
+function HasGraphicsHead(w::MathLink.WExpr)
+    HeadString = w.head.name
+    ###Check for graphics related names not based on ending on Plot* or Chart*
+    if in(w.head, graphics)
+        return  true
+    end
+
+    HeadsEndsWith(HeadString,"Plot") && return true
+    HeadsEndsWith(HeadString,"Chart") && return true
+    HeadsEndsWith(HeadString,"Plot3D") && return true
+    HeadsEndsWith(HeadString,"Chart3D") && return true
+    return false
+end
+
+import Base.show
+Base.Multimedia.showable(::MIME"text/latex", w::MathLink.WSymbol) = MLtexOutput
+Base.show(io,::MIME"text/latex",x::MathLink.WSymbol) = print(io,"\$"*W2Tex(x)*"\$")
+
+import Base.Multimedia.showable
+function Base.Multimedia.showable(::MIME"text/latex", w::MathLink.WExpr)
+    if !MLtexOutput
+        return false
+    end
+    if HasRecursiveGraphicsHead(w)
+        return false
+    else
+        return true
+    end
+end
+function Base.show(io,::MIME"text/latex",x::MathLink.WExpr)
+    print(io,"\$"*W2Tex(x)*"\$")
+end
+
+
+

test/runtests.jl

@@ -3,6 +3,8 @@ using Test
 
 import MathLink: WExpr, WSymbol
 
+
+
 @testset "integers" begin
     w = W"Factorial"(30)
     @test_throws MathLink.MathLinkError weval(Int, w)
@@ -182,3 +184,52 @@ end
     P14 * Mat
     P14 * Mat* P14
 end
+
+
+
+
+@testset  "Find Graphiscs" begin
+    @test !HasGraphicsHead(W"a")
+    @test HasGraphicsHead(W`Plot[x,{x,0,1}]`)
+    @test HasGraphicsHead(W`ListPlot[x,{x,0,1}]`)
+    @test HasGraphicsHead(W`ListLinePlot3D[x,{x,0,1}]`)
+    @test HasGraphicsHead(W`Plot3D[x,{x,0,1}]`)
+    @test !HasGraphicsHead(W"a"+W"b")
+    @test HasGraphicsHead(weval(W`Plot[x,{x,0,1}]`))
+    @test !HasGraphicsHead(W`{Plot[x,{x,0,1}],Plot[x^2,{x,0,1}]}`)
+    @test !HasGraphicsHead(weval(W`{Plot[x,{x,0,1}],Plot[x^2,{x,0,1}]}`))
+
+    @test !HasRecursiveGraphicsHead(W`{2,a+v,{4+d}}`)
+    @test HasRecursiveGraphicsHead(W`Plot[x,{x,0,1}]`)
+    @test HasRecursiveGraphicsHead(W`{2,Plot[x^2,{x,0,1}]}`)
+    @test HasRecursiveGraphicsHead(W`{a+b,Plot[x^2,{x,0,1}]}`)
+    @test HasRecursiveGraphicsHead(W`{Plot[x,{x,0,1}],Plot[x^2,{x,0,1}]}`)
+    @test HasRecursiveGraphicsHead(W`{1,{Plot[x,{x,0,1}],Plot[x^2,{x,0,1}]}}`)
+    @test HasRecursiveGraphicsHead(weval(W`{Plot[x,{x,0,1}],Plot[x^2,{x,0,1}]}`))
+end
+
+
+
+@testset "W2Tex - LaTex conversion" begin
+    @test W2Tex(W`(a+b)^(b+x)`) == "(a+b)^{b+x}"
+    @test W2Tex(W`a`) == "a"
+    @test W2Tex(W`ab`) == "\\text{ab}"
+    @test W2Tex(W`ab*cd`) == "\\text{ab} \\text{cd}"
+
+   
+    ###Testing that MIME form exists for the text/latex option of show.
+    io = IOBuffer();
+    ioc = IOContext(io, :limit => true, :displaysize => (10, 10)) 
+    show(ioc,"text/plain",W"a")
+    @test String(take!(io)) == "W\"a\""
+    show(ioc,"text/plain",W"a"+W"b")
+    @test String(take!(io)) == "W\"Plus\"(W\"a\", W\"b\")"
+
+    set_texOutput(true)
+    show(ioc,"text/latex",W"a"+W"b")
+    @test String(take!(io)) == "\$a+b\$"
+    @test showable("text/latex",W"a"+W"b")
+    set_texOutput(false)
+    @test !showable("text/latex",W"a"+W"b")
+end
+