Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

No more ImaginaryUnit: const im = Complex(false,true). #5468

Merged
merged 4 commits into from
Jan 22, 2014
Merged

No more ImaginaryUnit: const im = Complex(false,true). #5468

Show file tree
Hide file tree
Changes from 1 commit
Commits
Show all changes
4 commits
Select commit Hold shift + click to select a range
efcb565
No more ImaginaryUnit: `const im = Complex(false,true)`.
StefanKarpinski Jan 22, 2014
3e8ba28
base/complex.jl: show Complex{Bool}s as e.g. `Complex(true,false)`.
StefanKarpinski Jan 22, 2014
95bb03d
base/complex.jl: additional incidental cleanup and simplifications.
StefanKarpinski Jan 22, 2014
7bd82cf
base/bool.jl: false * -2.0 => -0.0, false * 2.0 => 0.0
StefanKarpinski Jan 22, 2014
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
6 changes: 6 additions & 0 deletions base/bool.jl
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -42,6 +42,12 @@ abs2(x::Bool) = x
^(x::Bool, y::Bool) = x|!y
^(x::Integer, y::Bool) = y ? x : one(x)

function *{T<:Number}(x::Bool, y::T)
S = promote_type(Bool,T)
ifelse(x, convert(S,y), convert(S,0))
Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Just curious, why the use of ifelse here?

Copy link
Sponsor Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

It doesn't require a branch --- both clauses can be evaluated, which often allows better code generation.

Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Thanks!

end
*(y::Number, x::Bool) = x * y

div(x::Bool, y::Bool) = y ? x : throw(DivideError())
fld(x::Bool, y::Bool) = div(x,y)
rem(x::Bool, y::Bool) = y ? false : throw(DivideError())
Expand Down
55 changes: 15 additions & 40 deletions base/complex.jl
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -5,6 +5,8 @@ end
Complex(x::Real, y::Real) = Complex(promote(x,y)...)
Complex(x::Real) = Complex(x, zero(x))

const im = Complex(false,true)

typealias Complex128 Complex{Float64}
typealias Complex64 Complex{Float32}
typealias Complex32 Complex{Float16}
Expand Down Expand Up @@ -57,24 +59,20 @@ isfinite(z::Complex) = isfinite(real(z)) && isfinite(imag(z))
reim(z) = (real(z), imag(z))

function complex_show(io::IO, z::Complex, compact::Bool)
z === im && return print(io, "im")
r, i = reim(z)
if isnan(r) || isfinite(i)
compact ? showcompact(io,r) : show(io,r)
if signbit(i)==1 && !isnan(i)
i = -i
print(io, compact ? "-" : " - ")
else
print(io, compact ? "+" : " + ")
end
compact ? showcompact(io, i) : show(io, i)
if !(isa(i,Integer) || isa(i,Rational) ||
isa(i,FloatingPoint) && isfinite(i))
print(io, "*")
end
print(io, "im")
compact ? showcompact(io,r) : show(io,r)
if signbit(i)==1 && !isnan(i)
i = -i
print(io, compact ? "-" : " - ")
else
print(io, "complex(",r,",",i,")")
print(io, compact ? "+" : " + ")
end
compact ? showcompact(io, i) : show(io, i)
if !(isa(i,Integer) && !isa(i,Bool) || isa(i,FloatingPoint) && isfinite(i))
print(io, "*")
end
print(io, "im")
end
show(io::IO, z::Complex) = complex_show(io, z, false)
showcompact(io::IO, z::Complex) = complex_show(io, z, true)
Expand All @@ -90,23 +88,6 @@ function write(s::IO, z::Complex)
end


## singleton type for imaginary unit constant ##

type ImaginaryUnit <: Number end
const im = ImaginaryUnit()

convert{T<:Real}(::Type{Complex{T}}, ::ImaginaryUnit) = Complex{T}(zero(T),one(T))
convert(::Type{Complex}, ::ImaginaryUnit) = Complex(real(im),imag(im))

real(::ImaginaryUnit) = int(0)
imag(::ImaginaryUnit) = int(1)

promote_rule{T<:Complex}(::Type{ImaginaryUnit}, ::Type{T}) = T
promote_rule{T<:Real}(::Type{ImaginaryUnit}, ::Type{T}) = Complex{T}

show(io::IO, ::ImaginaryUnit) = print(io, "im")


## generic functions of complex numbers ##

convert(::Type{Complex}, z::Complex) = z
Expand All @@ -127,28 +108,22 @@ inv(z::Complex) = conj(z)/abs2(z)
inv{T<:Integer}(z::Complex{T}) = inv(float(z))
sign(z::Complex) = z/abs(z)

(-)(::ImaginaryUnit) = complex(0, -1)
-(z::Complex) = complex(-real(z), -imag(z))
+(z::Complex, w::Complex) = complex(real(z) + real(w), imag(z) + imag(w))
-(z::Complex, w::Complex) = complex(real(z) - real(w), imag(z) - imag(w))
*(z::Complex, w::Complex) = complex(real(z) * real(w) - imag(z) * imag(w),
real(z) * imag(w) + imag(z) * real(w))

# adding or multiplying real & complex is common
*(x::Bool, z::Complex) = ifelse(x,z,zero(z))
*(z::Complex, x::Bool) = x * z
*(x::Real, z::Complex) = complex(x * real(z), x * imag(z))
*(z::Complex, x::Real) = complex(x * real(z), x * imag(z))
+(x::Real, z::Complex) = complex(x + real(z), imag(z))
+(z::Complex, x::Real) = complex(x + real(z), imag(z))
-(x::Real, z::Complex) = complex(x - real(z), -imag(z))
-(z::Complex, x::Real) = complex(real(z) - x, imag(z))

# multiplying by im is common
*(z::ImaginaryUnit, w::ImaginaryUnit) = complex(-imag(z), real(z))
*(z::ImaginaryUnit, x::Real) = complex(zero(x), x)
*(x::Real, z::ImaginaryUnit) = complex(zero(x), x)
*(z::ImaginaryUnit, w::Complex) = complex(-imag(w), real(w))
*(w::Complex, z::ImaginaryUnit) = complex(-imag(w), real(w))

/(z::Number, w::Complex) = z*inv(w)
/(a::Real , w::Complex) = a*inv(w)
/(z::Complex, x::Real) = complex(real(z)/x, imag(z)/x)
Expand Down
3 changes: 0 additions & 3 deletions base/constants.jl
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -18,9 +18,6 @@ for op in {:+, :-, :*, :/, :^}
@eval $op(x::MathConst, y::MathConst) = $op(float64(x),float64(y))
end

*(x::MathConst, i::ImaginaryUnit) = float64(x)*i
*(i::ImaginaryUnit, x::MathConst) = i*float64(x)

macro math_const(sym, val, def)
esym = esc(sym)
qsym = esc(Expr(:quote, sym))
Expand Down
1 change: 0 additions & 1 deletion base/exports.jl
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -51,7 +51,6 @@ export
GeneralizedSVD,
Hermitian,
Hessenberg,
ImaginaryUnit,
InsertionSort,
IntSet,
IO,
Expand Down