# This file is a part of Julia. License is MIT: https://julialang.org/license
module Sort
using Base: Order, Checked, copymutable, linearindices, IndexStyle, viewindexing, IndexLinear, _length, WritableRandomAccess
import
Base.sort,
Base.sort!,
Base.issorted,
Base.sortperm,
Base.Slice,
Base.to_indices
export # also exported by Base
# order-only:
issorted,
select,
select!,
searchsorted,
searchsortedfirst,
searchsortedlast,
# order & algorithm:
sort,
sort!,
selectperm,
selectperm!,
sortperm,
sortperm!,
sortrows,
sortcols,
# algorithms:
InsertionSort,
QuickSort,
MergeSort,
PartialQuickSort
export # not exported by Base
Algorithm,
DEFAULT_UNSTABLE,
DEFAULT_STABLE,
SMALL_ALGORITHM,
SMALL_THRESHOLD
## functions requiring only ordering ##
function issorted(itr, order::Ordering)
state = start(itr)
done(itr,state) && return true
prev, state = next(itr, state)
while !done(itr, state)
this, state = next(itr, state)
lt(order, this, prev) && return false
prev = this
end
return true
end
"""
issorted(v, lt=isless, by=identity, rev:Bool=false, order::Ordering=Forward)
Test whether a vector is in sorted order. The `lt`, `by` and `rev` keywords modify what
order is considered to be sorted just as they do for [`sort`](@ref).
```jldoctest
julia> issorted([1, 2, 3])
true
julia> issorted([(1, "b"), (2, "a")], by = x -> x[1])
true
julia> issorted([(1, "b"), (2, "a")], by = x -> x[2])
false
julia> issorted([(1, "b"), (2, "a")], by = x -> x[2], rev=true)
true
```
"""
issorted(itr;
lt=isless, by=identity, rev::Bool=false, order::Ordering=Forward) =
issorted(itr, ord(lt,by,rev,order))
function select!(v::AbstractVector, k::Union{Int,OrdinalRange}, o::Ordering)
inds = indices(v, 1)
sort!(v, first(inds), last(inds), PartialQuickSort(k), o)
v[k]
end
select!(v::AbstractVector, k::Union{Int,OrdinalRange};
lt=isless, by=identity, rev::Bool=false, order::Ordering=Forward) =
select!(v, k, ord(lt,by,rev,order))
select(v::AbstractVector, k::Union{Int,OrdinalRange}; kws...) = select!(copymutable(v), k; kws...)
# reference on sorted binary search:
# http://www.tbray.org/ongoing/When/200x/2003/03/22/Binary
# index of the first value of vector a that is greater than or equal to x;
# returns length(v)+1 if x is greater than all values in v.
function searchsortedfirst(v::AbstractVector, x, lo::Int, hi::Int, o::Ordering)
lo = lo-1
hi = hi+1
@inbounds while lo < hi-1
m = (lo+hi)>>>1
if lt(o, v[m], x)
lo = m
else
hi = m
end
end
return hi
end
# index of the last value of vector a that is less than or equal to x;
# returns 0 if x is less than all values of v.
function searchsortedlast(v::AbstractVector, x, lo::Int, hi::Int, o::Ordering)
lo = lo-1
hi = hi+1
@inbounds while lo < hi-1
m = (lo+hi)>>>1
if lt(o, x, v[m])
hi = m
else
lo = m
end
end
return lo
end
# returns the range of indices of v equal to x
# if v does not contain x, returns a 0-length range
# indicating the insertion point of x
function searchsorted(v::AbstractVector, x, ilo::Int, ihi::Int, o::Ordering)
lo = ilo-1
hi = ihi+1
@inbounds while lo < hi-1
m = (lo+hi)>>>1
if lt(o, v[m], x)
lo = m
elseif lt(o, x, v[m])
hi = m
else
a = searchsortedfirst(v, x, max(lo,ilo), m, o)
b = searchsortedlast(v, x, m, min(hi,ihi), o)
return a : b
end
end
return (lo + 1) : (hi - 1)
end
function searchsortedlast(a::Range{<:Real}, x::Real, o::DirectOrdering)
if step(a) == 0
lt(o, x, first(a)) ? 0 : length(a)
else
n = round(Integer, clamp((x - first(a)) / step(a) + 1, 1, length(a)))
lt(o, x, a[n]) ? n - 1 : n
end
end
function searchsortedfirst(a::Range{<:Real}, x::Real, o::DirectOrdering)
if step(a) == 0
lt(o, first(a), x) ? length(a) + 1 : 1
else
n = round(Integer, clamp((x - first(a)) / step(a) + 1, 1, length(a)))
lt(o, a[n] ,x) ? n + 1 : n
end
end
function searchsortedlast(a::Range{<:Integer}, x::Real, o::DirectOrdering)
if step(a) == 0
lt(o, x, first(a)) ? 0 : length(a)
else
clamp( fld(floor(Integer, x) - first(a), step(a)) + 1, 0, length(a))
end
end
function searchsortedfirst(a::Range{<:Integer}, x::Real, o::DirectOrdering)
if step(a) == 0
lt(o, first(a), x) ? length(a)+1 : 1
else
clamp(-fld(floor(Integer, -x) + first(a), step(a)) + 1, 1, length(a) + 1)
end
end
function searchsortedfirst(a::Range{<:Integer}, x::Unsigned, o::DirectOrdering)
if lt(o, first(a), x)
if step(a) == 0
length(a) + 1
else
min(cld(x - first(a), step(a)), length(a)) + 1
end
else
1
end
end
function searchsortedlast(a::Range{<:Integer}, x::Unsigned, o::DirectOrdering)
if lt(o, x, first(a))
0
elseif step(a) == 0
length(a)
else
min(fld(x - first(a), step(a)) + 1, length(a))
end
end
searchsorted(a::Range{<:Real}, x::Real, o::DirectOrdering) =
searchsortedfirst(a, x, o) : searchsortedlast(a, x, o)
for s in [:searchsortedfirst, :searchsortedlast, :searchsorted]
@eval begin
$s(v::AbstractVector, x, o::Ordering) = (inds = indices(v, 1); $s(v,x,first(inds),last(inds),o))
$s(v::AbstractVector, x;
lt=isless, by=identity, rev::Bool=false, order::Ordering=Forward) =
$s(v,x,ord(lt,by,rev,order))
$s(v::AbstractVector, x) = $s(v, x, Forward)
end
end
## sorting algorithms ##
abstract type Algorithm end
struct InsertionSortAlg <: Algorithm end
struct QuickSortAlg <: Algorithm end
struct MergeSortAlg <: Algorithm end
struct PartialQuickSort{T <: Union{Int,OrdinalRange}} <: Algorithm
k::T
end
Base.first(a::PartialQuickSort{Int}) = 1
Base.last(a::PartialQuickSort{Int}) = a.k
Base.first(a::PartialQuickSort) = first(a.k)
Base.last(a::PartialQuickSort) = last(a.k)
const InsertionSort = InsertionSortAlg()
const QuickSort = QuickSortAlg()
const MergeSort = MergeSortAlg()
const DEFAULT_UNSTABLE = QuickSort
const DEFAULT_STABLE = MergeSort
const SMALL_ALGORITHM = InsertionSort
const SMALL_THRESHOLD = 20
function sort!(v, lo::Int, hi::Int, ::InsertionSortAlg, o::Ordering)
@inbounds for i = lo+1:hi
j = i
x = v[i]
while j > lo
if lt(o, x, v[j-1])
v[j] = v[j-1]
j -= 1
continue
end
break
end
v[j] = x
end
return v
end
# selectpivot!
#
# Given 3 locations in an array (lo, mi, and hi), sort v[lo], v[mi], v[hi]) and
# choose the middle value as a pivot
#
# Upon return, the pivot is in v[lo], and v[hi] is guaranteed to be
# greater than the pivot
@inline function selectpivot!(v, lo::Int, hi::Int, o::Ordering)
@inbounds begin
mi = (lo+hi)>>>1
# sort the values in v[lo], v[mi], v[hi]
if lt(o, v[mi], v[lo])
v[mi], v[lo] = v[lo], v[mi]
end
if lt(o, v[hi], v[mi])
if lt(o, v[hi], v[lo])
v[lo], v[mi], v[hi] = v[hi], v[lo], v[mi]
else
v[hi], v[mi] = v[mi], v[hi]
end
end
# move v[mi] to v[lo] and use it as the pivot
v[lo], v[mi] = v[mi], v[lo]
pivot = v[lo]
end
# return the pivot
return pivot
end
# partition!
#
# select a pivot, and partition v according to the pivot
function partition!(v, lo::Int, hi::Int, o::Ordering)
pivot = selectpivot!(v, lo, hi, o)
# pivot == v[lo], v[hi] > pivot
i, j = lo, hi
@inbounds while true
i += 1; j -= 1
while lt(o, v[i], pivot); i += 1; end;
while lt(o, pivot, v[j]); j -= 1; end;
i >= j && break
v[i], v[j] = v[j], v[i]
end
v[j], v[lo] = pivot, v[j]
# v[j] == pivot
# v[k] >= pivot for k > j
# v[i] <= pivot for i < j
return j
end
function sort!(v, lo::Int, hi::Int, a::QuickSortAlg, o::Ordering)
@inbounds while lo < hi
hi-lo <= SMALL_THRESHOLD && return sort!(v, lo, hi, SMALL_ALGORITHM, o)
j = partition!(v, lo, hi, o)
if j-lo < hi-j
# recurse on the smaller chunk
# this is necessary to preserve O(log(n))
# stack space in the worst case (rather than O(n))
lo < (j-1) && sort!(v, lo, j-1, a, o)
lo = j+1
else
j+1 < hi && sort!(v, j+1, hi, a, o)
hi = j-1
end
end
return v
end
function sort!(v, lo::Int, hi::Int, a::MergeSortAlg, o::Ordering, t=similar(v,0))
@inbounds if lo < hi
hi-lo <= SMALL_THRESHOLD && return sort!(v, lo, hi, SMALL_ALGORITHM, o)
m = (lo+hi)>>>1
(length(t) < m-lo+1) && resize!(t, m-lo+1)
sort!(v, lo, m, a, o, t)
sort!(v, m+1, hi, a, o, t)
i, j = 1, lo
while j <= m
t[i] = v[j]
i += 1
j += 1
end
i, k = 1, lo
while k < j <= hi
if lt(o, v[j], t[i])
v[k] = v[j]
j += 1
else
v[k] = t[i]
i += 1
end
k += 1
end
while k < j
v[k] = t[i]
k += 1
i += 1
end
end
return v
end
## TODO: When PartialQuickSort is parameterized by an Int, this version of sort
## has one less comparison per loop than the version below, but enabling
## it causes return type inference to fail for sort/sort! (#12833)
##
# function sort!(v::AbstractVector, lo::Int, hi::Int, a::PartialQuickSort{Int},
# o::Ordering)
# @inbounds while lo < hi
# hi-lo <= SMALL_THRESHOLD && return sort!(v, lo, hi, SMALL_ALGORITHM, o)
# j = partition!(v, lo, hi, o)
# if j >= a.k
# # we don't need to sort anything bigger than j
# hi = j-1
# elseif j-lo < hi-j
# # recurse on the smaller chunk
# # this is necessary to preserve O(log(n))
# # stack space in the worst case (rather than O(n))
# lo < (j-1) && sort!(v, lo, j-1, a, o)
# lo = j+1
# else
# (j+1) < hi && sort!(v, j+1, hi, a, o)
# hi = j-1
# end
# end
# return v
# end
function sort!(v, lo::Int, hi::Int, a::PartialQuickSort,
o::Ordering)
@inbounds while lo < hi
hi-lo <= SMALL_THRESHOLD && return sort!(v, lo, hi, SMALL_ALGORITHM, o)
j = partition!(v, lo, hi, o)
if j <= first(a)
lo = j+1
elseif j >= last(a)
hi = j-1
else
if j-lo < hi-j
lo < (j-1) && sort!(v, lo, j-1, a, o)
lo = j+1
else
hi > (j+1) && sort!(v, j+1, hi, a, o)
hi = j-1
end
end
end
return v
end
## generic sorting methods ##
defalg(v) = defalg(eltype(v))
defalg(::Type) = DEFAULT_STABLE
defalg(::Type{<:Number}) = DEFAULT_UNSTABLE
sort!(v, alg::Algorithm, order::Ordering) = sort!(v, Base.iteratoraccess(v), alg, order)
sort!(v, access, alg::Algorithm, order::Ordering) = throw(ArgumentError("the collection must have setindex! defined"))
function sort!(v, ::WritableRandomAccess, alg::Algorithm, order::Ordering)
inds = linearindices(v)
sort!(v,first(inds),last(inds),alg,order)
end
"""
sort!(v; alg::Algorithm=defalg(v), lt=isless, by=identity, rev::Bool=false, order::Ordering=Forward)
Sort the vector `v` in place. `QuickSort` is used by default for numeric arrays while
`MergeSort` is used for other arrays. You can specify an algorithm to use via the `alg`
keyword (see Sorting Algorithms for available algorithms). The `by` keyword lets you provide
a function that will be applied to each element before comparison; the `lt` keyword allows
providing a custom "less than" function; use `rev=true` to reverse the sorting order. These
options are independent and can be used together in all possible combinations: if both `by`
and `lt` are specified, the `lt` function is applied to the result of the `by` function;
`rev=true` reverses whatever ordering specified via the `by` and `lt` keywords.
```jldoctest
julia> v = [3, 1, 2]; sort!(v); v
3-element Array{Int64,1}:
1
2
3
julia> v = [3, 1, 2]; sort!(v, rev = true); v
3-element Array{Int64,1}:
3
2
1
julia> v = [(1, "c"), (3, "a"), (2, "b")]; sort!(v, by = x -> x[1]); v
3-element Array{Tuple{Int64,String},1}:
(1, "c")
(2, "b")
(3, "a")
julia> v = [(1, "c"), (3, "a"), (2, "b")]; sort!(v, by = x -> x[2]); v
3-element Array{Tuple{Int64,String},1}:
(3, "a")
(2, "b")
(1, "c")
```
"""
function sort!(v;
alg::Algorithm=defalg(v),
lt=isless,
by=identity,
rev::Bool=false,
order::Ordering=Forward)
ordr = ord(lt,by,rev,order)
if ordr === Forward && isa(v,Vector) && eltype(v)<:Integer
n = _length(v)
if n > 1
min, max = extrema(v)
(diff, o1) = sub_with_overflow(max, min)
(rangelen, o2) = add_with_overflow(diff, oneunit(diff))
if !o1 && !o2 && rangelen < div(n,2)
return sort_int_range!(v, rangelen, min)
end
end
end
sort!(v, alg, ordr)
end
# sort! for vectors of few unique integers
function sort_int_range!(x::Vector{<:Integer}, rangelen, minval)
offs = 1 - minval
n = length(x)
where = fill(0, rangelen)
@inbounds for i = 1:n
where[x[i] + offs] += 1
end
idx = 1
@inbounds for i = 1:rangelen
lastidx = idx + where[i] - 1
val = i-offs
for j = idx:lastidx
x[j] = val
end
idx = lastidx + 1
end
return x
end
"""
sort(v; alg::Algorithm=defalg(v), lt=isless, by=identity, rev::Bool=false, order::Ordering=Forward)
Variant of [`sort!`](@ref) that returns a sorted copy of `v` leaving `v` itself unmodified.
```jldoctest
julia> v = [3, 1, 2];
julia> sort(v)
3-element Array{Int64,1}:
1
2
3
julia> v
3-element Array{Int64,1}:
3
1
2
```
"""
sort(v; kws...) = sort!(copymutable(v); kws...)
## selectperm: the permutation to sort the first k elements of an array ##
selectperm(v::AbstractVector, k::Union{Integer,OrdinalRange}; kwargs...) =
selectperm!(similar(Vector{eltype(k)}, indices(v,1)), v, k; kwargs..., initialized=false)
function selectperm!(ix::AbstractVector{<:Integer}, v::AbstractVector,
k::Union{Int, OrdinalRange};
lt::Function=isless,
by::Function=identity,
rev::Bool=false,
order::Ordering=Forward,
initialized::Bool=false)
if !initialized
@inbounds for i = indices(ix,1)
ix[i] = i
end
end
# do partial quicksort
sort!(ix, PartialQuickSort(k), Perm(ord(lt, by, rev, order), v))
return ix[k]
end
## sortperm: the permutation to sort an array ##
"""
sortperm(v; alg::Algorithm=DEFAULT_UNSTABLE, lt=isless, by=identity, rev::Bool=false, order::Ordering=Forward)
Return a permutation vector of indices of `v` that puts it in sorted order. Specify `alg` to
choose a particular sorting algorithm (see Sorting Algorithms). `MergeSort` is used by
default, and since it is stable, the resulting permutation will be the lexicographically
first one that puts the input array into sorted order – i.e. indices of equal elements
appear in ascending order. If you choose a non-stable sorting algorithm such as `QuickSort`,
a different permutation that puts the array into order may be returned. The order is
specified using the same keywords as `sort!`.
See also [`sortperm!`](@ref).
```jldoctest
julia> v = [3, 1, 2];
julia> p = sortperm(v)
3-element Array{Int64,1}:
2
3
1
julia> v[p]
3-element Array{Int64,1}:
1
2
3
```
"""
function sortperm(v::AbstractVector;
alg::Algorithm=DEFAULT_UNSTABLE,
lt=isless,
by=identity,
rev::Bool=false,
order::Ordering=Forward)
ordr = ord(lt,by,rev,order)
if ordr === Forward && isa(v,Vector) && eltype(v)<:Integer
n = _length(v)
if n > 1
min, max = extrema(v)
(diff, o1) = sub_with_overflow(max, min)
(rangelen, o2) = add_with_overflow(diff, oneunit(diff))
if !o1 && !o2 && rangelen < div(n,2)
return sortperm_int_range(v, rangelen, min)
end
end
end
p = similar(Vector{Int}, indices(v, 1))
for (i,ind) in zip(eachindex(p), indices(v, 1))
p[i] = ind
end
sort!(p, alg, Perm(ordr,v))
end
"""
sortperm!(ix, v; alg::Algorithm=DEFAULT_UNSTABLE, lt=isless, by=identity, rev::Bool=false, order::Ordering=Forward, initialized::Bool=false)
Like [`sortperm`](@ref), but accepts a preallocated index vector `ix`. If `initialized` is `false`
(the default), `ix` is initialized to contain the values `1:length(v)`.
```jldoctest
julia> v = [3, 1, 2]; p = zeros(Int, 3);
julia> sortperm!(p, v); p
3-element Array{Int64,1}:
2
3
1
julia> v[p]
3-element Array{Int64,1}:
1
2
3
```
"""
function sortperm!(x::AbstractVector{<:Integer}, v::AbstractVector;
alg::Algorithm=DEFAULT_UNSTABLE,
lt=isless,
by=identity,
rev::Bool=false,
order::Ordering=Forward,
initialized::Bool=false)
if indices(x,1) != indices(v,1)
throw(ArgumentError("index vector must have the same indices as the source vector, $(indices(x,1)) != $(indices(v,1))"))
end
if !initialized
@inbounds for i = indices(v,1)
x[i] = i
end
end
sort!(x, alg, Perm(ord(lt,by,rev,order),v))
end
# sortperm for vectors of few unique integers
function sortperm_int_range(x::Vector{<:Integer}, rangelen, minval)
offs = 1 - minval
n = length(x)
where = fill(0, rangelen+1)
where[1] = 1
@inbounds for i = 1:n
where[x[i] + offs + 1] += 1
end
cumsum!(where, where)
P = Vector{Int}(n)
@inbounds for i = 1:n
label = x[i] + offs
P[where[label]] = i
where[label] += 1
end
return P
end
## sorting multi-dimensional arrays ##
"""
sort(A, dim::Integer; alg::Algorithm=DEFAULT_UNSTABLE, lt=isless, by=identity, rev::Bool=false, order::Ordering=Forward, initialized::Bool=false)
Sort a multidimensional array `A` along the given dimension.
See [`sort!`](@ref) for a description of possible
keyword arguments.
```jldoctest
julia> A = [4 3; 1 2]
2×2 Array{Int64,2}:
4 3
1 2
julia> sort(A, 1)
2×2 Array{Int64,2}:
1 2
4 3
julia> sort(A, 2)
2×2 Array{Int64,2}:
3 4
1 2
```
"""
function sort(A::AbstractArray, dim::Integer;
alg::Algorithm=DEFAULT_UNSTABLE,
lt=isless,
by=identity,
rev::Bool=false,
order::Ordering=Forward,
initialized::Bool=false)
order = ord(lt,by,rev,order)
n = length(indices(A, dim))
if dim != 1
pdims = (dim, setdiff(1:ndims(A), dim)...) # put the selected dimension first
Ap = permutedims(A, pdims)
Av = vec(Ap)
sort_chunks!(Av, n, alg, order)
permutedims(Ap, invperm(pdims))
else
Av = A[:]
sort_chunks!(Av, n, alg, order)
reshape(Av, indices(A))
end
end
@noinline function sort_chunks!(Av, n, alg, order)
inds = linearindices(Av)
for s = first(inds):n:last(inds)
sort!(Av, s, s+n-1, alg, order)
end
Av
end
"""
sortrows(A; alg::Algorithm=DEFAULT_UNSTABLE, lt=isless, by=identity, rev::Bool=false, order::Ordering=Forward)
Sort the rows of matrix `A` lexicographically.
See [`sort!`](@ref) for a description of possible
keyword arguments.
# Examples
```jldoctest
julia> sortrows([7 3 5; -1 6 4; 9 -2 8])
3×3 Array{Int64,2}:
-1 6 4
7 3 5
9 -2 8
julia> sortrows([7 3 5; -1 6 4; 9 -2 8], lt=(x,y)->isless(x[2],y[2]))
3×3 Array{Int64,2}:
9 -2 8
7 3 5
-1 6 4
julia> sortrows([7 3 5; -1 6 4; 9 -2 8], rev=true)
3×3 Array{Int64,2}:
9 -2 8
7 3 5
-1 6 4
```
"""
function sortrows(A::AbstractMatrix; kws...)
inds = indices(A,1)
T = slicetypeof(A, inds, :)
rows = similar(Vector{T}, indices(A, 1))
for i in inds
rows[i] = view(A, i, :)
end
p = sortperm(rows; kws..., order=Lexicographic)
A[p,:]
end
"""
sortcols(A; alg::Algorithm=DEFAULT_UNSTABLE, lt=isless, by=identity, rev::Bool=false, order::Ordering=Forward)
Sort the columns of matrix `A` lexicographically.
See [`sort!`](@ref) for a description of possible
keyword arguments.
# Examples
```jldoctest
julia> sortcols([7 3 5; 6 -1 -4; 9 -2 8])
3×3 Array{Int64,2}:
3 5 7
-1 -4 6
-2 8 9
julia> sortcols([7 3 5; 6 -1 -4; 9 -2 8], alg=InsertionSort, lt=(x,y)->isless(x[2],y[2]))
3×3 Array{Int64,2}:
5 3 7
-4 -1 6
8 -2 9
julia> sortcols([7 3 5; 6 -1 -4; 9 -2 8], rev=true)
3×3 Array{Int64,2}:
7 5 3
6 -4 -1
9 8 -2
```
"""
function sortcols(A::AbstractMatrix; kws...)
inds = indices(A,2)
T = slicetypeof(A, :, inds)
cols = similar(Vector{T}, indices(A, 2))
for i in inds
cols[i] = view(A, :, i)
end
p = sortperm(cols; kws..., order=Lexicographic)
A[:,p]
end
function slicetypeof(A::AbstractArray{T}, i1, i2) where T
I = map(slice_dummy, to_indices(A, (i1, i2)))
fast = isa(IndexStyle(viewindexing(I), IndexStyle(A)), IndexLinear)
SubArray{T,1,typeof(A),typeof(I),fast}
end
slice_dummy(S::Slice) = S
slice_dummy(::AbstractUnitRange{T}) where {T} = oneunit(T)
## fast clever sorting for floats ##
module Float
using ..Sort
using ...Order
import Core.Intrinsics: slt_int
import ..Sort: sort!
import ...Order: lt, DirectOrdering
const Floats = Union{Float32,Float64}
struct Left <: Ordering end
struct Right <: Ordering end
left(::DirectOrdering) = Left()
right(::DirectOrdering) = Right()
left(o::Perm) = Perm(left(o.order), o.data)
right(o::Perm) = Perm(right(o.order), o.data)
lt(::Left, x::T, y::T) where {T<:Floats} = slt_int(y, x)
lt(::Right, x::T, y::T) where {T<:Floats} = slt_int(x, y)
isnan(o::DirectOrdering, x::Floats) = (x!=x)
isnan(o::Perm, i::Int) = isnan(o.order,o.data[i])
function nans2left!(v::AbstractVector, o::Ordering, lo::Int=first(indices(v,1)), hi::Int=last(indices(v,1)))
i = lo
@inbounds while i <= hi && isnan(o,v[i])
i += 1
end
j = i + 1
@inbounds while j <= hi
if isnan(o,v[j])
v[i], v[j] = v[j], v[i]
i += 1
end
j += 1
end
return i, hi
end
function nans2right!(v::AbstractVector, o::Ordering, lo::Int=first(indices(v,1)), hi::Int=last(indices(v,1)))
i = hi
@inbounds while lo <= i && isnan(o,v[i])
i -= 1
end
j = i - 1
@inbounds while lo <= j
if isnan(o,v[j])
v[i], v[j] = v[j], v[i]
i -= 1
end
j -= 1
end
return lo, i
end
nans2end!(v::AbstractVector, o::ForwardOrdering) = nans2right!(v,o)
nans2end!(v::AbstractVector, o::ReverseOrdering) = nans2left!(v,o)
nans2end!(v::AbstractVector{Int}, o::Perm{<:ForwardOrdering}) = nans2right!(v,o)
nans2end!(v::AbstractVector{Int}, o::Perm{<:ReverseOrdering}) = nans2left!(v,o)
issignleft(o::ForwardOrdering, x::Floats) = lt(o, x, zero(x))
issignleft(o::ReverseOrdering, x::Floats) = lt(o, x, -zero(x))
issignleft(o::Perm, i::Int) = issignleft(o.order, o.data[i])
function fpsort!(v::AbstractVector, a::Algorithm, o::Ordering)
i, j = lo, hi = nans2end!(v,o)
@inbounds while true
while i <= j && issignleft(o,v[i]); i += 1; end
while i <= j && !issignleft(o,v[j]); j -= 1; end
i <= j || break
v[i], v[j] = v[j], v[i]
i += 1; j -= 1
end
sort!(v, lo, j, a, left(o))
sort!(v, i, hi, a, right(o))
return v
end
fpsort!(v::AbstractVector, a::Sort.PartialQuickSort, o::Ordering) =
sort!(v, first(indices(v,1)), last(indices(v,1)), a, o)
sort!(v::AbstractVector{<:Floats}, a::Algorithm, o::DirectOrdering) = fpsort!(v,a,o)
sort!(v::Vector{Int}, a::Algorithm, o::Perm{<:DirectOrdering,<:Vector{<:Floats}}) = fpsort!(v,a,o)
end # module Sort.Float
end # module Sort