Add methods for getcoeff involving tuples

docs/src/examples.md

@@ -112,7 +112,7 @@ We note that the above functions use expansions in `Int128`. This is actually
 required, since some coefficients are larger than `typemax(Int)`:
 
 ```@repl fateman
-getcoeff(f2, [1,6,7,20]) # coefficient of x y^6 z^7 w^{20}
+getcoeff(f2, (1,6,7,20)) # coefficient of x y^6 z^7 w^{20}
 ans > typemax(Int)
 length(f2)
 sum(TaylorSeries.size_table)

docs/src/userguide.md

@@ -304,11 +304,12 @@ exy = exp(x+y)
 
 The function [`getcoeff`](@ref)
 gives the normalized coefficient of the polynomial that corresponds to the
-monomial specified by a vector `v` containing the powers. For instance, for
+monomial specified by the tuple or vector `v` containing the powers.
+For instance, for
 the polynomial `exy` above, the coefficient of the monomial ``x^3 y^5`` is
-
+obtained using `getcoeff(exy, (3,5))` or `getcoeff(exy, [3,5])`.
 ```@repl userguide
-getcoeff(exy, [3,5])
+getcoeff(exy, (3,5))
 rationalize(ans)
 ```
 

src/auxiliary.jl

@@ -94,15 +94,17 @@ setindex!(a::Taylor1{T}, x::Array{T,1}, c::Colon) where {T<:Number} = a.coeffs[c
 """
     getcoeff(a, v)
 
-Return the coefficient of `a::HomogeneousPolynomial`, specified by
-`v::Array{Int,1}` which has the indices of the specific monomial.
+Return the coefficient of `a::HomogeneousPolynomial`, specified by `v`,
+which is a tuple (or vector) with the indices of the specific
+monomial.
 """
-function getcoeff(a::HomogeneousPolynomial, v::Array{Int,1})
-    @assert length(v) == get_numvars()
+function getcoeff(a::HomogeneousPolynomial, v::NTuple{N,Int}) where {N}
+    @assert N == get_numvars() && all(v .>= 0)
     kdic = in_base(get_order(),v)
     @inbounds n = pos_table[a.order+1][kdic]
     a[n]
 end
+getcoeff(a::HomogeneousPolynomial, v::Array{Int,1}) = getcoeff(a, (v...,))
 
 getindex(a::HomogeneousPolynomial, n::Int) = a.coeffs[n]
 getindex(a::HomogeneousPolynomial, n::UnitRange) = view(a.coeffs, n)
@@ -123,14 +125,16 @@ setindex!(a::HomogeneousPolynomial{T}, x::Array{T,1}, c::Colon) where {T<:Number
 """
     getcoeff(a, v)
 
-Return the coefficient of `a::TaylorN`, specified by
-`v::Array{Int,1}` which has the indices of the specific monomial.
+Return the coefficient of `a::TaylorN`, specified by `v`,
+which is a tuple (or vector) with the indices of the specific
+monomial.
 """
-function getcoeff(a::TaylorN, v::Array{Int,1})
+function getcoeff(a::TaylorN, v::NTuple{N, Int}) where {N}
     order = sum(v)
     @assert order ≤ a.order
     getcoeff(a[order], v)
 end
+getcoeff(a::TaylorN, v::Array{Int,1}) = getcoeff(a, (v...,))
 
 getindex(a::TaylorN, n::Int) = a.coeffs[n+1]
 getindex(a::TaylorN, u::UnitRange) = view(a.coeffs, u .+ 1)

test/manyvariables.jl

@@ -97,8 +97,8 @@ end
     @test get_order(zeroT) == 1
     @test xT[1][1] == 1
     @test yH[2] == 1
-    @test getcoeff(xT,[1,0]) == 1
-    @test getcoeff(yH,[1,0]) == 0
+    @test getcoeff(xT,(1,0)) == getcoeff(xT,[1,0]) == 1
+    @test getcoeff(yH,(1,0)) == getcoeff(yH,[1,0]) == 0
     @test typeof(convert(HomogeneousPolynomial,1im)) ==
         HomogeneousPolynomial{Complex{Int}}
     @test convert(HomogeneousPolynomial,1im) ==
@@ -307,10 +307,10 @@ end
     @test conj(im*yH) == (im*yH)'
     @test conj(im*yT) == (im*yT)'
     @test real( exp(1im * xT)) == cos(xT)
-    @test getcoeff(convert(TaylorN{Rational{Int}},cos(xT)),[4,0]) ==
+    @test getcoeff(convert(TaylorN{Rational{Int}},cos(xT)),(4,0)) ==
         1//factorial(4)
     cr = convert(TaylorN{Rational{Int}},cos(xT))
-    @test getcoeff(cr,[4,0]) == 1//factorial(4)
+    @test getcoeff(cr,(4,0)) == 1//factorial(4)
     @test imag((exp(yT))^(-1im)') == sin(yT)
     exy = exp( xT+yT )
     @test evaluate(exy) == 1
@@ -323,7 +323,7 @@ end
     @test isapprox(evaluate(exy, (1,1)), eeuler^2)
     @test exy(:x₁, 0.0) == exp(yT)
     txy = tan(xT+yT)
-    @test getcoeff(txy,[8,7]) == 929569/99225
+    @test getcoeff(txy,(8,7)) == 929569/99225
     ptxy = xT + yT + (1/3)*( xT^3 + yT^3 ) + xT^2*yT + xT*yT^2
     @test getindex(tan(TaylorN(1)+TaylorN(2)),0:4) == ptxy.coeffs[1:5]
     @test evaluate(xH*yH, 1.0, 2.0) == (xH*yH)(1.0, 2.0) == 2.0