https://github.com/JuliaLang/julia
Tip revision: 0c24dca65c031820b91721139f0291068086955c authored by Elliot Saba on 17 February 2015, 22:12:25 UTC
Tag v0.3.6
Tag v0.3.6
Tip revision: 0c24dca
math.jl
module Math
export sin, cos, tan, sinh, cosh, tanh, asin, acos, atan,
asinh, acosh, atanh, sec, csc, cot, asec, acsc, acot,
sech, csch, coth, asech, acsch, acoth,
sinpi, cospi, sinc, cosc,
cosd, cotd, cscd, secd, sind, tand,
acosd, acotd, acscd, asecd, asind, atand, atan2,
rad2deg, deg2rad,
log, log2, log10, log1p, exponent, exp, exp2, exp10, expm1,
cbrt, sqrt, erf, erfc, erfcx, erfi, dawson,
ceil, floor, trunc, round, significand,
lgamma, hypot, gamma, lfact, max, min, minmax, ldexp, frexp,
clamp, modf, ^, mod2pi,
airy, airyai, airyprime, airyaiprime, airybi, airybiprime, airyx,
besselj0, besselj1, besselj, besseljx,
bessely0, bessely1, bessely, besselyx,
hankelh1, hankelh2, hankelh1x, hankelh2x,
besseli, besselix, besselk, besselkx, besselh,
beta, lbeta, eta, zeta, polygamma, invdigamma, digamma, trigamma,
erfinv, erfcinv, @evalpoly
import Base: log, exp, sin, cos, tan, sinh, cosh, tanh, asin,
acos, atan, asinh, acosh, atanh, sqrt, log2, log10,
max, min, minmax, ceil, floor, trunc, round, ^, exp2,
exp10, expm1, log1p
import Core.Intrinsics: nan_dom_err, sqrt_llvm, box, unbox, powi_llvm
# non-type specific math functions
clamp{X,L,H}(x::X, lo::L, hi::H) =
ifelse(x > hi, convert(promote_type(X,L,H), hi),
ifelse(x < lo,
convert(promote_type(X,L,H), lo),
convert(promote_type(X,L,H), x)))
clamp{T}(x::AbstractArray{T,1}, lo, hi) = [clamp(xx, lo, hi) for xx in x]
clamp{T}(x::AbstractArray{T,2}, lo, hi) =
[clamp(x[i,j], lo, hi) for i in 1:size(x,1), j in 1:size(x,2)]
clamp{T}(x::AbstractArray{T}, lo, hi) =
reshape([clamp(xx, lo, hi) for xx in x], size(x))
# evaluate p[1] + x * (p[2] + x * (....)), i.e. a polynomial via Horner's rule
macro horner(x, p...)
ex = esc(p[end])
for i = length(p)-1:-1:1
ex = :($(esc(p[i])) + t * $ex)
end
Expr(:block, :(t = $(esc(x))), ex)
end
# Evaluate p[1] + z*p[2] + z^2*p[3] + ... + z^(n-1)*p[n]. This uses
# Horner's method if z is real, but for complex z it uses a more
# efficient algorithm described in Knuth, TAOCP vol. 2, section 4.6.4,
# equation (3).
macro evalpoly(z, p...)
a = :($(esc(p[end])))
b = :($(esc(p[end-1])))
as = {}
for i = length(p)-2:-1:1
ai = symbol(string("a", i))
push!(as, :($ai = $a))
a = :($b + r*$ai)
b = :($(esc(p[i])) - s * $ai)
end
ai = :a0
push!(as, :($ai = $a))
C = Expr(:block,
:(t = $(esc(z))),
:(x = real(t)),
:(y = imag(t)),
:(r = x + x),
:(s = x*x + y*y),
as...,
:($ai * t + $b))
R = Expr(:macrocall, symbol("@horner"), esc(z), p...)
:(isa($(esc(z)), Complex) ? $C : $R)
end
rad2deg(z::Real) = oftype(z, 57.29577951308232*z)
deg2rad(z::Real) = oftype(z, 0.017453292519943295*z)
rad2deg(z::Integer) = rad2deg(float(z))
deg2rad(z::Integer) = deg2rad(float(z))
@vectorize_1arg Real rad2deg
@vectorize_1arg Real deg2rad
log(b,x) = log(x)./log(b)
# type specific math functions
const libm = Base.libm_name
const openspecfun = "libopenspecfun"
# functions with no domain error
for f in (:cbrt, :sinh, :cosh, :tanh, :atan, :asinh, :exp, :erf, :erfc, :exp2, :expm1)
@eval begin
($f)(x::Float64) = ccall(($(string(f)),libm), Float64, (Float64,), x)
($f)(x::Float32) = ccall(($(string(f,"f")),libm), Float32, (Float32,), x)
($f)(x::Real) = ($f)(float(x))
@vectorize_1arg Number $f
end
end
# fallback definitions to prevent infinite loop from $f(x::Real) def above
cbrt(x::FloatingPoint) = x^(1//3)
exp2(x::FloatingPoint) = 2^x
for f in (:sinh, :cosh, :tanh, :atan, :asinh, :exp, :erf, :erfc, :expm1)
@eval ($f)(x::FloatingPoint) = error("not implemented for ", typeof(x))
end
# TODO: GNU libc has exp10 as an extension; should openlibm?
exp10(x::Float64) = 10.0^x
exp10(x::Float32) = 10.0f0^x
exp10(x::Integer) = exp10(float(x))
@vectorize_1arg Number exp10
# functions that return NaN on non-NaN argument for domain error
for f in (:sin, :cos, :tan, :asin, :acos, :acosh, :atanh, :log, :log2, :log10,
:lgamma, :log1p)
@eval begin
($f)(x::Float64) = nan_dom_err(ccall(($(string(f)),libm), Float64, (Float64,), x), x)
($f)(x::Float32) = nan_dom_err(ccall(($(string(f,"f")),libm), Float32, (Float32,), x), x)
($f)(x::Real) = ($f)(float(x))
@vectorize_1arg Number $f
end
end
sqrt(x::Float64) = box(Float64,sqrt_llvm(unbox(Float64,x)))
sqrt(x::Float32) = box(Float32,sqrt_llvm(unbox(Float32,x)))
sqrt(x::Real) = sqrt(float(x))
@vectorize_1arg Number sqrt
for f in (:ceil, :trunc, :significand) # :rint, :nearbyint
@eval begin
($f)(x::Float64) = ccall(($(string(f)),libm), Float64, (Float64,), x)
($f)(x::Float32) = ccall(($(string(f,"f")),libm), Float32, (Float32,), x)
@vectorize_1arg Real $f
end
end
round(x::Float32) = ccall((:roundf, libm), Float32, (Float32,), x)
@vectorize_1arg Real round
floor(x::Float32) = ccall((:floorf, libm), Float32, (Float32,), x)
@vectorize_1arg Real floor
hypot(x::Real, y::Real) = hypot(promote(float(x), float(y))...)
function hypot{T<:FloatingPoint}(x::T, y::T)
x = abs(x)
y = abs(y)
if x < y
x, y = y, x
end
if x == 0
r = y/one(x)
else
r = y/x
if isnan(r)
isinf(x) && return x
isinf(y) && return y
return r
end
end
x * sqrt(one(r)+r*r)
end
atan2(y::Real, x::Real) = atan2(promote(float(y),float(x))...)
atan2{T<:FloatingPoint}(y::T, x::T) = Base.no_op_err("atan2", T)
for f in (:atan2, :hypot)
@eval begin
($f)(y::Float64, x::Float64) = ccall(($(string(f)),libm), Float64, (Float64, Float64,), y, x)
($f)(y::Float32, x::Float32) = ccall(($(string(f,"f")),libm), Float32, (Float32, Float32), y, x)
@vectorize_2arg Number $f
end
end
max{T<:FloatingPoint}(x::T, y::T) = ifelse((y > x) | (x != x), y, x)
@vectorize_2arg Real max
min{T<:FloatingPoint}(x::T, y::T) = ifelse((y < x) | (x != x), y, x)
@vectorize_2arg Real min
minmax{T<:FloatingPoint}(x::T, y::T) = x <= y ? (x, y) :
x > y ? (y, x) :
x == x ? (x, x) : (y, y)
function exponent(x::Float64)
if x==0 || !isfinite(x)
throw(DomainError())
end
int(ccall((:ilogb,libm), Int32, (Float64,), x))
end
function exponent(x::Float32)
if x==0 || !isfinite(x)
throw(DomainError())
end
int(ccall((:ilogbf,libm), Int32, (Float32,), x))
end
@vectorize_1arg Real exponent
ldexp(x::Float64,e::Int) = ccall((:scalbn,libm), Float64, (Float64,Int32), x, int32(e))
ldexp(x::Float32,e::Int) = ccall((:scalbnf,libm), Float32, (Float32,Int32), x, int32(e))
# TODO: vectorize ldexp
begin
local exp::Array{Int32,1} = zeros(Int32,1)
global frexp
function frexp(x::Float64)
s = ccall((:frexp,libm), Float64, (Float64, Ptr{Int32}), x, exp)
(s, int(exp[1]))
end
function frexp(x::Float32)
s = ccall((:frexpf,libm), Float32, (Float32, Ptr{Int32}), x, exp)
(s, int(exp[1]))
end
function frexp(A::Array{Float64})
f = similar(A)
e = Array(Int, size(A))
for i = 1:length(A)
f[i] = ccall((:frexp,libm), Float64, (Float64, Ptr{Int32}), A[i], exp)
e[i] = exp[1]
end
return (f, e)
end
function frexp(A::Array{Float32})
f = similar(A)
e = Array(Int, size(A))
for i = 1:length(A)
f[i] = ccall((:frexpf,libm), Float32, (Float32, Ptr{Int32}), A[i], exp)
e[i] = exp[1]
end
return (f, e)
end
end
modf(x) = rem(x,one(x)), trunc(x)
const _modff_temp = Float32[0]
function modf(x::Float32)
f = ccall((:modff,libm), Float32, (Float32,Ptr{Float32}), x, _modff_temp)
f, _modff_temp[1]
end
const _modf_temp = Float64[0]
function modf(x::Float64)
f = ccall((:modf,libm), Float64, (Float64,Ptr{Float64}), x, _modf_temp)
f, _modf_temp[1]
end
^(x::Float64, y::Float64) = nan_dom_err(ccall((:pow,libm), Float64, (Float64,Float64), x, y), x+y)
^(x::Float32, y::Float32) = nan_dom_err(ccall((:powf,libm), Float32, (Float32,Float32), x, y), x+y)
^(x::Float64, y::Integer) =
box(Float64, powi_llvm(unbox(Float64,x), unbox(Int32,int32(y))))
^(x::Float32, y::Integer) =
box(Float32, powi_llvm(unbox(Float32,x), unbox(Int32,int32(y))))
function angle_restrict_symm(theta)
const P1 = 4 * 7.8539812564849853515625e-01
const P2 = 4 * 3.7748947079307981766760e-08
const P3 = 4 * 2.6951514290790594840552e-15
y = 2*floor(theta/(2*pi))
r = ((theta - y*P1) - y*P2) - y*P3
if (r > pi)
r -= (2*pi)
end
return r
end
## mod2pi-related calculations ##
function add22condh(xh::Float64, xl::Float64, yh::Float64, yl::Float64)
# as above, but only compute and return high double
r = xh+yh
s = (abs(xh) > abs(yh)) ? (xh-r+yh+yl+xl) : (yh-r+xh+xl+yl)
zh = r+s
return zh
end
function ieee754_rem_pio2(x::Float64)
# rem_pio2 essentially computes x mod pi/2 (ie within a quarter circle)
# and returns the result as
# y between + and - pi/4 (for maximal accuracy (as the sign bit is exploited)), and
# n, where n specifies the integer part of the division, or, at any rate,
# in which quadrant we are.
# The invariant fulfilled by the returned values seems to be
# x = y + n*pi/2 (where y = y1+y2 is a double-double and y2 is the "tail" of y).
# Note: for very large x (thus n), the invariant might hold only modulo 2pi
# (in other words, n might be off by a multiple of 4, or a multiple of 100)
# this is just wrapping up
# https://github.com/JuliaLang/openspecfun/blob/master/rem_pio2/e_rem_pio2.c
y = [0.0,0.0]
n = ccall((:__ieee754_rem_pio2, openspecfun), Cint, (Float64,Ptr{Float64}), x, y)
return (n,y)
end
# multiples of pi/2, as double-double (ie with "tail")
const pi1o2_h = 1.5707963267948966 # convert(Float64, pi * BigFloat(1/2))
const pi1o2_l = 6.123233995736766e-17 # convert(Float64, pi * BigFloat(1/2) - pi1o2_h)
const pi2o2_h = 3.141592653589793 # convert(Float64, pi * BigFloat(1))
const pi2o2_l = 1.2246467991473532e-16 # convert(Float64, pi * BigFloat(1) - pi2o2_h)
const pi3o2_h = 4.71238898038469 # convert(Float64, pi * BigFloat(3/2))
const pi3o2_l = 1.8369701987210297e-16 # convert(Float64, pi * BigFloat(3/2) - pi3o2_h)
const pi4o2_h = 6.283185307179586 # convert(Float64, pi * BigFloat(2))
const pi4o2_l = 2.4492935982947064e-16 # convert(Float64, pi * BigFloat(2) - pi4o2_h)
function mod2pi(x::Float64) # or modtau(x)
# with r = mod2pi(x)
# a) 0 <= r < 2π (note: boundary open or closed - a bit fuzzy, due to rem_pio2 implementation)
# b) r-x = k*2π with k integer
# note: mod(n,4) is 0,1,2,3; while mod(n-1,4)+1 is 1,2,3,4.
# We use the latter to push negative y in quadrant 0 into the positive (one revolution, + 4*pi/2)
if x < pi4o2_h
if 0.0 <= x return x end
if x > -pi4o2_h
return add22condh(x,0.0,pi4o2_h,pi4o2_l)
end
end
(n,y) = ieee754_rem_pio2(x)
if iseven(n)
if n & 2 == 2 # add pi
return add22condh(y[1],y[2],pi2o2_h,pi2o2_l)
else # add 0 or 2pi
if y[1] > 0.0
return y[1]
else # else add 2pi
return add22condh(y[1],y[2],pi4o2_h,pi4o2_l)
end
end
else # add pi/2 or 3pi/2
if n & 2 == 2 # add 3pi/2
return add22condh(y[1],y[2],pi3o2_h,pi3o2_l)
else # add pi/2
return add22condh(y[1],y[2],pi1o2_h,pi1o2_l)
end
end
end
mod2pi(x::Float32) = float32(mod2pi(float64(x)))
mod2pi(x::Int32) = mod2pi(float64(x))
function mod2pi(x::Int64)
fx = float64(x)
fx == x || error("Integer argument to mod2pi is too large: $x")
mod2pi(fx)
end
# More special functions
include("special/trig.jl")
include("special/bessel.jl")
include("special/erf.jl")
include("special/gamma.jl")
end # module