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Static arrays #10

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Oct 16, 2017
Merged

Static arrays #10

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1 change: 1 addition & 0 deletions REQUIRE
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Original file line number Diff line number Diff line change
@@ -1 +1,2 @@
julia 0.5
StaticArrays 0.3.1
85 changes: 16 additions & 69 deletions src/SkyCoords.jl
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@@ -1,12 +1,13 @@
module SkyCoords
using StaticArrays

export AbstractSkyCoords,
ICRSCoords,
GalCoords,
FK5Coords,
separation

import Base: convert, *, transpose
import Base: convert

# -----------------------------------------------------------------------------
# Types
Expand Down Expand Up @@ -44,60 +45,6 @@ end
#(::Type{FK5Coords{e}}){e}(ra::Real, dec::Real) =
# FK5Coords{e}(promote(float(ra), float(dec))...)

# -----------------------------------------------------------------------------
# Helper functions: Immutable array operations

# We use immutable array operations to avoid allocating memory for
# small arrays. Eventually, base Julia should support immutable arrays, at
# which point we should switch to using that functionality in base.

immutable Matrix33{T<:AbstractFloat}
a11::T
a12::T
a13::T
a21::T
a22::T
a23::T
a31::T
a32::T
a33::T
end

(::Type{Matrix33{T}}){T}(m::Matrix33{T}) = m
(::Type{Matrix33{T}}){T}(m::Matrix33) =
Matrix33(T(m.a11), T(m.a12), T(m.a13),
T(m.a21), T(m.a22), T(m.a23),
T(m.a31), T(m.a32), T(m.a33))

immutable Vector3{T<:AbstractFloat}
x::T
y::T
z::T
end

function *(x::Matrix33, y::Matrix33)
Matrix33(x.a11 * y.a11 + x.a12 * y.a21 + x.a13 * y.a31,
x.a11 * y.a12 + x.a12 * y.a22 + x.a13 * y.a32,
x.a11 * y.a13 + x.a12 * y.a23 + x.a13 * y.a33,
x.a21 * y.a11 + x.a22 * y.a21 + x.a23 * y.a31,
x.a21 * y.a12 + x.a22 * y.a22 + x.a23 * y.a32,
x.a21 * y.a13 + x.a22 * y.a23 + x.a23 * y.a33,
x.a31 * y.a11 + x.a32 * y.a21 + x.a33 * y.a31,
x.a31 * y.a12 + x.a32 * y.a22 + x.a33 * y.a32,
x.a31 * y.a13 + x.a32 * y.a23 + x.a33 * y.a33)
end

transpose(m::Matrix33) = Matrix33(m.a11, m.a21, m.a31,
m.a12, m.a22, m.a32,
m.a13, m.a23, m.a33)

function *(m::Matrix33, v::Vector3)
Vector3(m.a11 * v.x + m.a12 * v.y + m.a13 * v.z,
m.a21 * v.x + m.a22 * v.y + m.a23 * v.z,
m.a31 * v.x + m.a32 * v.y + m.a33 * v.z)
end


# -----------------------------------------------------------------------------
# Helper functions: Create rotation matrix about a given axis (x, y, z)

Expand All @@ -107,34 +54,34 @@ end

function xrotmat(angle)
s, c = sincos(angle)
Matrix33(1., 0., 0.,
0., c, s,
0., -s, c)
SMatrix{3,3}(1, 0, 0,
0, c, -s,
0, s, c)
end

function yrotmat(angle)
s, c = sincos(angle)
Matrix33(c, 0., -s,
0., 1., 0.,
s, 0., c)
SMatrix{3,3}( c, 0, s,
0, 1, 0,
-s, 0, c)
end

function zrotmat(angle)
s, c = sincos(angle)
Matrix33(c, s, 0.,
-s, c, 0.,
0., 0., 1.)
SMatrix{3,3}(c, -s, 0,
s, c, 0,
0, 0, 1)
end

# (lon, lat) -> [x, y, z] unit vector
function coords2cart(lon, lat)
sinlon, coslon = sincos(lon)
sinlat, coslat = sincos(lat)
Vector3(coslat * coslon, coslat * sinlon, sinlat)
SVector{3}(coslat * coslon, coslat * sinlon, sinlat)
end

# [x, y, z] unit vector -> (lon, lat)
cart2coords(v) = atan2(v.y, v.x), atan2(v.z, sqrt(v.x*v.x + v.y*v.y))
cart2coords(v) = atan2(v[2], v[1]), atan2(v[3], sqrt(v[1] * v[1] + v[2] * v[2]))

# -----------------------------------------------------------------------------
# Constant rotation matricies and precession matrix function
Expand Down Expand Up @@ -206,7 +153,7 @@ lat(c::AbstractSkyCoords) = c.dec
coords2cart(c::AbstractSkyCoords) = coords2cart(lon(c), lat(c))

# Rotation matrix between coordinate systems: `rotmat(to, from)`
# Note that all of these return Matrix33{Float64}, regardless of
# Note that all of these return SMatrix{3,3}{Float64}, regardless of
# element type of input coordinates.
rotmat{T1<:GalCoords, T2<:ICRSCoords}(::Type{T1}, ::Type{T2}) = ICRS_TO_GAL
rotmat{T1<:ICRSCoords, T2<:GalCoords}(::Type{T1}, ::Type{T2}) = GAL_TO_ICRS
Expand Down Expand Up @@ -244,7 +191,7 @@ _eltype(c::AbstractSkyCoords) = _eltype(typeof(c))
# Scalar coordinate conversions
convert{T<:AbstractSkyCoords}(::Type{T}, c::T) = c
function convert{T<:AbstractSkyCoords, S<:AbstractSkyCoords}(::Type{T}, c::S)
r = Matrix33{_eltype(c)}(rotmat(T, S)) * coords2cart(c)
r = SMatrix{3,3}{_eltype(c)}(rotmat(T, S)) * coords2cart(c)
lon, lat = cart2coords(r)
T(lon, lat)
end
Expand All @@ -257,7 +204,7 @@ end
convert{T<:AbstractSkyCoords,n}(::Type{Array{T,n}}, c::Array{T,n}) = c
function convert{T<:AbstractSkyCoords, n, S<:AbstractSkyCoords}(
::Type{Array{T,n}}, c::Array{S, n})
m = Matrix33{_eltype(S)}(rotmat(T, S))
m = SMatrix{3,3}{_eltype(S)}(rotmat(T, S))
result = similar(c, T)
for i in 1:length(c)
r = m * coords2cart(c[i])
Expand Down
2 changes: 1 addition & 1 deletion test/runtests.jl
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Expand Up @@ -9,7 +9,7 @@ import SkyCoords: lat, lon

datapath = joinpath(dirname(@__FILE__), "data")

rad2arcsec(r) = 3600.*rad2deg(r)
rad2arcsec(r) = 3600 * rad2deg(r)

# input coordinates
fname = joinpath(datapath, "input_coords.csv")
Expand Down