Merge pull request #192 from cdsousa/master

Fix CSE for scalar and array cases

Author: jverzani

src/simplify.jl

@@ -2,7 +2,7 @@
 ## from http://docs.sympy.org/0.7.2/modules/simplify/simplify.html
 
 ## simple methods (x, args) -> y (y coercion happens via PyCall)
-simplify_sympy_meths = (:collect, :rcollect, :separate, 
+simplify_sympy_meths = (:collect, :rcollect, :separate,
                         :separatevars,
                         :radsimp, :ratsimp, :trigsimp, :besselsimp,
                         :powsimp, :combsimp, :hypersimp,
@@ -11,7 +11,7 @@ simplify_sympy_meths = (:collect, :rcollect, :separate,
                         :posify, :powdenest, :sqrtdenest,
                         :logcombine, :hyperexpand)
 
-                            
+
 expand_sympy_meths = (:expand_trig,
                       :expand_power_base, :expand_power_exp,
                       :expand_log,
@@ -32,13 +32,9 @@ Example: (from man page)
 cse(((w + x + y + z)*(w + y + z))/(w + x)^3), ([(x0, y + z), (x1, w + x)], [(w + x0)*(x0 + x1)/x1^3]) # tuple of replacements and reduced expressions.
 
 """ ->
-cse{T<:SymbolicObject}(ex::T, args...; kwargs...) = sympy_meth(:cse, ex, args...; kwargs...)
-cse{T<:SymbolicObject}(ex::Vector{T}, args...; kwargs...) = sympy_meth(:cse, ex, args...; kwargs...)
-        
-function cse{T<:SymbolicObject, N}(ex::AbstractArray{T, N}, args...; kwargs...)
-    a,b = cse(ex[:], args...; kwargs...)
-    bb = convert(Array{Sym},  reshape(b, size(ex)))
-    a, bb
+function cse{T<:SymbolicObject}(ex::Union{T, AbstractArray{T}}, args...; kwargs...)
+    a, b = sympy_meth(:cse, ex, args...; kwargs...)
+    a, oftype(ex, b[1])
 end
 export(cse)
 

test/tests.jl

@@ -178,7 +178,7 @@ end
     @vars a b; eqs = (a*x+2y-3, 2b*x + 3y - 4)
     as = linsolve(eqs, x, y)
     @test length(elements(as)) == 1
-    
+
     ## limits
     @test limit(x -> sin(x)/x, 0) == 1
     @test limit(sin(x)/x, x, 0) |> float == 1
@@ -475,6 +475,12 @@ end
     @test round(y, 5) == 0
     @test round(y, 16) != 0
 
+    ## test cse output
+    @test cse(x) == (Any[], x)
+    @test cse([x]) == (Any[], [x])
+    @test cse([x, x]) == (Any[], [x, x])
+    @test cse([x x; x x]) == (Any[], [x x; x x])
+
 ## sympy"..."(...)
 @vars x
 @test sympy"sin"(1) == sin(Sym(1))