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{{task|Sorting Algorithms}} {{Sorting Algorithm}}
;Task: Sort an integer array with the [[wp:Radix sort|radix sort algorithm]].
The primary purpose is to complete the characterization of sort algorithms task.
Ada
radix_sort.adb:
with Ada.Text_IO;
procedure Radix_Sort is
type Integer_Array is array (Positive range <>) of Integer;
procedure Least_Significant_Radix_Sort (Data : in out Integer_Array; Base : Positive := 10) is
type Bucket is record
Count : Natural := 0;
Content : Integer_Array (Data'Range);
end record;
subtype Bucket_Index is Integer range -Base + 1 .. Base - 1;
type Bucket_Array is array (Bucket_Index) of Bucket;
procedure Append (To : in out Bucket; Item : Integer) is
begin
To.Count := To.Count + 1;
To.Content (To.Count) := Item;
end Append;
function Get_Nth_Digit (Value : Integer; N : Positive) return Integer is
Result : Integer := (Value / (Base ** (N - 1))) mod Base;
begin
if Value < 0 then
Result := -Result;
end if;
return Result;
end Get_Nth_Digit;
function Get_Maximum return Natural is
Result : Natural := 0;
begin
for I in Data'Range loop
if abs (Data (I)) > Result then
Result := abs (Data (I));
end if;
end loop;
return Result;
end Get_Maximum;
function Split (Pass : Positive) return Bucket_Array is
Buckets : Bucket_Array;
begin
for I in Data'Range loop
Append (To => Buckets (Get_Nth_Digit (Data (I), Pass)),
Item => Data (I));
end loop;
return Buckets;
end Split;
function Merge (Buckets : Bucket_Array) return Integer_Array is
Result : Integer_Array (Data'Range);
Current_Index : Positive := 1;
begin
for Sublist in Buckets'Range loop
for Item in 1 .. Buckets (Sublist).Count loop
Result (Current_Index) := Buckets (Sublist).Content (Item);
Current_Index := Current_Index + 1;
end loop;
end loop;
return Result;
end Merge;
Max_Number : Natural := Get_Maximum;
Digit_Count : Positive := 1;
begin
-- count digits of biggest number
while Max_Number > Base loop
Digit_Count := Digit_Count + 1;
Max_Number := Max_Number / Base;
end loop;
for Pass in 1 .. Digit_Count loop
Data := Merge (Split (Pass));
end loop;
end Least_Significant_Radix_Sort;
Test_Array : Integer_Array := (170, 45, 75, -90, -802, 24, 2, 66);
begin
Least_Significant_Radix_Sort (Test_Array, 4);
for I in Test_Array'Range loop
Ada.Text_IO.Put (Integer'Image (Test_Array (I)));
end loop;
Ada.Text_IO.New_Line;
end Radix_Sort;
output:
-802-90 2 24 45 66 75 170
ALGOL 68
PROC radixsort = (REF []INT array) VOID:
(
[UPB array]INT zero;
[UPB array]INT one;
BITS mask := 16r01;
INT zero_index := 0,
one_index := 0,
array_index := 1;
WHILE ABS(mask) > 0 DO
WHILE array_index <= UPB array DO
IF (BIN(array[array_index]) AND mask) = 16r0 THEN
zero_index +:= 1;
zero[zero_index] := array[array_index]
ELSE
one_index +:= 1;
one[one_index] := array[array_index]
FI;
array_index +:= 1
OD;
array_index := 1;
FOR i FROM 1 TO zero_index DO
array[array_index] := zero[i];
array_index +:= 1
OD;
FOR i FROM 1 TO one_index DO
array[array_index] := one[i];
array_index +:=1
OD;
array_index := 1;
zero_index := one_index := 0;
mask := mask SHL 1
OD
);
main:
(
[10]INT a;
FOR i FROM 1 TO UPB a DO
a[i] := ROUND(random*1000)
OD;
print(("Before:", a));
print((newline, newline));
radixsort(a);
print(("After: ", a))
)
{{out}}
Before: +459 +941 +623 +386 +263 +766 +129 +554 +160 +328
After: +129 +160 +263 +328 +386 +459 +554 +623 +766 +941
AutoHotkey
Radix_Sort(data){
loop, parse, data, `,
n := StrLen(A_LoopField)>n?StrLen(A_LoopField):n
loop % n {
bucket := [] , i := A_Index
loop, parse, data, `,
bucket[SubStr(A_LoopField,1-i)] .= (bucket[SubStr(A_LoopField,1-i)]?",":"") A_LoopField
data := ""
for i, v in bucket
data .= (data?",":"") v
}
return data
}
Examples:
d = 170,45,75,90,802,2,24,66
MsgBox, 262144, , % Radix_Sort(d)
Outputs:
2,24,45,66,75,90,170,802
BBC BASIC
{{works with|BBC BASIC for Windows}} The array index is assumed to start at zero. The third parameter of PROCradixsort() is the radix used.
DIM test%(9)
test%() = 4, 65, 2, -31, 0, 99, 2, 83, 782, 1
PROCradixsort(test%(), 10, 10)
FOR i% = 0 TO 9
PRINT test%(i%) ;
NEXT
PRINT
END
DEF PROCradixsort(a%(), n%, r%)
LOCAL d%, e%, i%, l%, m%, b%(), bucket%()
DIM b%(n%-1), bucket%(r%-1)
FOR i% = 0 TO n%-1
IF a%(i%) < l% l% = a%(i%)
IF a%(i%) > m% m% = a%(i%)
NEXT
a%() -= l%
m% -= l%
e% = 1
WHILE m% DIV e%
bucket%() = 0
FOR i% = 0 TO n%-1
bucket%(a%(i%) DIV e% MOD r%) += 1
NEXT
FOR i% = 1 TO r%-1
bucket%(i%) += bucket%(i% - 1)
NEXT
FOR i% = n%-1 TO 0 STEP -1
d% = a%(i%) DIV e% MOD r%
bucket%(d%) -= 1
b%(bucket%(d%)) = a%(i%)
NEXT
a%() = b%()
e% *= r%
ENDWHILE
a%() += l%
ENDPROC
'''Output:'''
-31 0 1 2 2 4 65 83 99 782
C
Radix sort, "digits" are most significant bits.
#include <stdio.h> #include <limits.h> #include <stdlib.h> #include <time.h> // Get size of statically allocated array #define ARR_LEN(ARR) (sizeof ARR / sizeof *ARR) // Generate random number in the interval [M,N] #define RAND_RNG(M,N) (M + rand() / (RAND_MAX / (N - M + 1) + 1)); static void swap(unsigned *a, unsigned *b) { unsigned tmp = *a; *a = *b; *b = tmp; } /* sort unsigned ints */ static void rad_sort_u(unsigned *from, unsigned *to, unsigned bit) { if (!bit || to < from + 1) return; unsigned *ll = from, *rr = to - 1; for (;;) { /* find left most with bit, and right most without bit, swap */ while (ll < rr && !(*ll & bit)) ll++; while (ll < rr && (*rr & bit)) rr--; if (ll >= rr) break; swap(ll, rr); } if (!(bit & *ll) && ll < to) ll++; bit >>= 1; rad_sort_u(from, ll, bit); rad_sort_u(ll, to, bit); } /* sort signed ints: flip highest bit, sort as unsigned, flip back */ static void radix_sort(int *a, const size_t len) { size_t i; unsigned *x = (unsigned*) a; for (i = 0; i < len; i++) x[i] ^= INT_MIN; rad_sort_u(x, x + len, INT_MIN); for (i = 0; i < len; i++) x[i] ^= INT_MIN; } int main(void) { srand(time(NULL)); int x[16]; for (size_t i = 0; i < ARR_LEN(x); i++) x[i] = RAND_RNG(-128,127) radix_sort(x, ARR_LEN(x)); for (size_t i = 0; i < ARR_LEN(x); i++) printf("%d%c", x[i], i + 1 < ARR_LEN(x) ? ' ' : '\n'); }
output
-182 -175 -151 -141 -70 -51 -20 -5 -1 41 70 103 171 198 227 242
C++
Implements a least significant digit radix sort and a recursive most significant digit radix sort.
Note: the LSD radix sort uses the standard library '''std::stable_partition''' algorithm. This algorithm is guaranteed to preserve relative order and has a higher runtime cost. The MSD radix sort uses '''std::partition''' and can be significantly faster.
#include <algorithm> #include <iostream> #include <iterator> // Radix sort comparator for 32-bit two's complement integers class radix_test { const int bit; // bit position [0..31] to examine public: radix_test(int offset) : bit(offset) {} // constructor bool operator()(int value) const // function call operator { if (bit == 31) // sign bit return value < 0; // negative int to left partition else return !(value & (1 << bit)); // 0 bit to left partition } }; // Least significant digit radix sort void lsd_radix_sort(int *first, int *last) { for (int lsb = 0; lsb < 32; ++lsb) // least-significant-bit { std::stable_partition(first, last, radix_test(lsb)); } } // Most significant digit radix sort (recursive) void msd_radix_sort(int *first, int *last, int msb = 31) { if (first != last && msb >= 0) { int *mid = std::partition(first, last, radix_test(msb)); msb--; // decrement most-significant-bit msd_radix_sort(first, mid, msb); // sort left partition msd_radix_sort(mid, last, msb); // sort right partition } } // test radix_sort int main() { int data[] = { 170, 45, 75, -90, -802, 24, 2, 66 }; lsd_radix_sort(data, data + 8); // msd_radix_sort(data, data + 8); std::copy(data, data + 8, std::ostream_iterator<int>(std::cout, " ")); return 0; }
Output:
-802 -90 2 24 45 66 75 170
C#
{{works with|C sharp|C#|3.0+}}
using System; namespace RadixSort { class Program { static void Sort(int[] old) { int i, j; int[] tmp = new int[old.Length]; for (int shift = 31; shift > -1; --shift) { j = 0; for (i = 0; i < old.Length; ++i) { bool move = (old[i] << shift) >= 0; if (shift == 0 ? !move : move) // shift the 0's to old's head old[i-j] = old[i]; else // move the 1's to tmp tmp[j++] = old[i]; } Array.Copy(tmp, 0, old, old.Length-j, j); } } static void Main(string[] args) { int[] old = new int[] { 2, 5, 1, -3, 4 }; Console.WriteLine(string.Join(", ", old)); Sort(old); Console.WriteLine(string.Join(", ", old)); Console.Read(); } } }
D
Shorter Version
import std.stdio, std.math, std.traits, std.range, std.algorithm; ElementType!R[] radixSort(size_t N=10, R)(R r) if (hasLength!R && isRandomAccessRange!R && isIntegral!(ElementType!R)) { alias ElementType!R E; static if (isDynamicArray!R) alias r res; // input is array => in place sort else E[] res = r.array(); // input is Range => return a new array E absMax = r.map!abs().reduce!max(); immutable nPasses = 1 + cast(int)(log(absMax) / log(N)); foreach (pass; 0 .. nPasses) { auto bucket = new E[][](2 * N - 1, 0); foreach (v; res) { int bIdx = abs(v / (N ^^ pass)) % N; bIdx = (v < 0) ? -bIdx : bIdx; bucket[N + bIdx - 1] ~= v; } res = bucket.join(); } return res; } void main() { auto items = [170, 45, 75, -90, 2, 24, -802, 66]; items.radixSort().writeln(); items.map!q{1 - a}().radixSort().writeln(); }
{{out}}
[-802, -90, 2, 24, 45, 66, 75, 170]
[-1, -23, -44, -65, -74, -169, 91, 803]
More Efficient Version
import std.array, std.traits; // considered pure for this program extern(C) void* alloca(in size_t length) pure nothrow; void radixSort(size_t MAX_ALLOCA=5_000, U)(U[] data) pure nothrow if (isUnsigned!U) { static void radix(in uint byteIndex, in U[] source, U[] dest) pure nothrow { immutable size_t sourceSize = source.length; ubyte* curByte = (cast(ubyte*)source.ptr) + byteIndex; uint[ubyte.max + 1] byteCounter; for (size_t i = 0; i < sourceSize; i++, curByte += U.sizeof) byteCounter[*curByte]++; { uint indexStart; foreach (uint i; 0 .. byteCounter.length) { immutable size_t tempCount = byteCounter[i]; byteCounter[i] = indexStart; indexStart += tempCount; } } curByte = (cast(ubyte*)source.ptr) + byteIndex; for (size_t i = 0; i < sourceSize; i++, curByte += U.sizeof) { uint* countPtr = byteCounter.ptr + *curByte; dest[*countPtr] = source[i]; (*countPtr)++; } } U[] tempData; if (U.sizeof * data.length <= MAX_ALLOCA) { U* ptr = cast(U*)alloca(data.length * U.sizeof); if (ptr != null) tempData = ptr[0 .. data.length]; } if (tempData.empty) tempData = uninitializedArray!(U[])(data.length); static if (U.sizeof == 1) { radix(0, data, tempData); data[] = tempData[]; } else { for (uint i = 0; i < U.sizeof; i += 2) { radix(i + 0, data, tempData); radix(i + 1, tempData, data); } } } void main() { import std.stdio; uint[] items = [170, 45, 75, 4294967206, 2, 24, 4294966494, 66]; items.radixSort(); writeln(items); }
{{out}}
[2, 24, 45, 66, 75, 170, 4294966494, 4294967206]
Original C++ code, modified (unknown license), by Andre Reinald, Paul Harris, Ryan Rohrer, Dirk Jagdmann: http://www.cubic.org/docs/download/radix_ar_2011.cpp
EasyLang
subr sort radix = 16 max = 0 for di range len data[] if data[di] > max max = data[di] . . len buck[][] radix pos = 1 while pos <= max for i range radix len buck[i][] 0 . for di range len data[] h = data[di] / pos mod radix buck[h][] &= data[di] . di = 0 for i range radix for j range len buck[i][] data[di] = buck[i][j] di += 1 . . pos *= radix . . data[] = [ 29 4 72 44 55 26 27 77 92 5 ] call sort print data[]
## Eiffel
Works for positive integers. Splits up into two buckets according to the binary representation of the number.
```Eiffel
class
RADIX_SORT
feature
radix_sort (ar: ARRAY [INTEGER])
-- Array 'ar' sorted in ascending order.
require
ar_not_void: ar /= Void
not_negative: across ar as a all a.item >= 0 end
local
bucket_1, bucket_0: LINKED_LIST [INTEGER]
j, k, dig: INTEGER
do
create bucket_0.make
create bucket_1.make
dig := digits (ar)
across
0 |..| dig as c
loop
across
ar as r
loop
if r.item.bit_test (c.item) then
bucket_1.extend (r.item)
else
bucket_0.extend (r.item)
end
end
from
j := 1
until
j > bucket_0.count
loop
ar [j] := bucket_0 [j]
j := j + 1
end
from
k := j
j := 1
until
j > bucket_1.count
loop
ar [k] := bucket_1 [j]
k := k + 1
j := j + 1
end
bucket_0.wipe_out
bucket_1.wipe_out
end
ensure
is_sorted: is_sorted (ar)
end
feature {NONE}
digits (ar: ARRAY [INTEGER]): INTEGER
-- Number of digits of the largest item in 'ar'.
local
max: INTEGER
math: DOUBLE_MATH
do
create math
across
ar as a
loop
if a.item > max then
max := a.item
end
end
Result := math.log_2 (max).ceiling + 1
end
is_sorted (ar: ARRAY [INTEGER]): BOOLEAN
--- Is 'ar' sorted in ascending order?
local
i: INTEGER
do
Result := True
from
i := ar.lower
until
i >= ar.upper
loop
if ar [i] > ar [i + 1] then
Result := False
end
i := i + 1
end
end
end
Test:
class
APPLICATION
create
make
feature
make
local
test: ARRAY [INTEGER]
do
create rs
create test.make_empty
test := <<5, 4, 999, 5, 70, 0, 1000, 55, 1, 2, 3>>
io.put_string ("Unsorted:%N")
across
test as t
loop
io.put_string (t.item.out + " ")
end
rs.radix_sort (test)
io.put_string ("%NSorted:%N")
across
test as t
loop
io.put_string (t.item.out + " ")
end
end
rs: RADIX_SORT
end
{{out}}
Unsorted:
5 4 999 5 70 0 1000 55 1 2 3
Sorted:
0 1 2 3 4 5 5 55 70 999 1000
Elixir
{{trans|Ruby}}
defmodule Sort do def radix_sort(list), do: radix_sort(list, 10) def radix_sort([], _), do: [] def radix_sort(list, base) do max = abs(Enum.max_by(list, &abs(&1))) sorted = radix_sort(list, base, max, 1) {minus, plus} = Enum.partition(sorted, &(&1<0)) Enum.reverse(minus, plus) end defp radix_sort(list, _, max, m) when max<m, do: list defp radix_sort(list, base, max, m) do buckets = List.to_tuple(for _ <- 0..base-1, do: []) bucket2 = Enum.reduce(list, buckets, fn x,acc -> i = abs(x) |> div(m) |> rem(base) put_elem(acc, i, [x | elem(acc, i)]) end) list2 = Enum.reduce(base-1..0, [], fn i,acc -> Enum.reverse(elem(bucket2, i), acc) end) radix_sort(list2, base, max, m*base) end end IO.inspect Sort.radix_sort([-4, 5, -26, 58, -990, 331, 331, 990, -1837, 2028])
{{out}}
[-1837, -990, -26, -4, 5, 58, 331, 331, 990, 2028]
Fortran
*
### =================================================================
* RSORT - sort a list of integers by the Radix Sort algorithm
* Public domain. This program may be used by any person for any purpose.
* Origin: Herman Hollerith, 1887
*
*___Name____Type______In/Out____Description_____________________________
* IX(N) Integer Both Array to be sorted in increasing order
* IW(N) Integer Neither Workspace
* N Integer In Length of array
*
* ASSUMPTIONS: Bits in an INTEGER is an even number.
* Integers are represented by twos complement.
*
* NOTE THAT: Radix sorting has an advantage when the input is known
* to be less than some value, so that only a few bits need
* to be compared. This routine looks at all the bits,
* and is thus slower than Quicksort.
*
### =================================================================
SUBROUTINE RSORT (IX, IW, N)
IMPLICIT NONE
INTEGER IX, IW, N
DIMENSION IX(N), IW(N)
INTEGER I, ! count bits
$ ILIM, ! bits in an integer
$ J, ! count array elements
$ P1OLD, P0OLD, P1, P0, ! indices to ones and zeros
$ SWAP
LOGICAL ODD ! even or odd bit position
* IF (N < 2) RETURN ! validate
*
ILIM = Bit_size(i) !Get the fixed number of bits
*
### =================================================================
* Alternate between putting data into IW and into IX
*
### =================================================================
P1 = N+1
P0 = N ! read from 1, N on first pass thru
ODD = .FALSE.
DO I = 0, ILIM-2
P1OLD = P1
P0OLD = P0 ! save the value from previous bit
P1 = N+1
P0 = 0 ! start a fresh count for next bit
IF (ODD) THEN
DO J = 1, P0OLD, +1 ! copy data from the zeros
IF ( BTEST(IW(J), I) ) THEN
P1 = P1 - 1
IX(P1) = IW(J)
ELSE
P0 = P0 + 1
IX(P0) = IW(J)
END IF
END DO
DO J = N, P1OLD, -1 ! copy data from the ones
IF ( BTEST(IW(J), I) ) THEN
P1 = P1 - 1
IX(P1) = IW(J)
ELSE
P0 = P0 + 1
IX(P0) = IW(J)
END IF
END DO
ELSE
DO J = 1, P0OLD, +1 ! copy data from the zeros
IF ( BTEST(IX(J), I) ) THEN
P1 = P1 - 1
IW(P1) = IX(J)
ELSE
P0 = P0 + 1
IW(P0) = IX(J)
END IF
END DO
DO J = N, P1OLD, -1 ! copy data from the ones
IF ( BTEST(IX(J), I) ) THEN
P1 = P1 - 1
IW(P1) = IX(J)
ELSE
P0 = P0 + 1
IW(P0) = IX(J)
END IF
END DO
END IF ! even or odd i
ODD = .NOT. ODD
END DO ! next i
*
### =================================================================
* the sign bit
*
### =================================================================
P1OLD = P1
P0OLD = P0
P1 = N+1
P0 = 0
* if sign bit is set, send to the zero end
DO J = 1, P0OLD, +1
IF ( BTEST(IW(J), ILIM-1) ) THEN
P0 = P0 + 1
IX(P0) = IW(J)
ELSE
P1 = P1 - 1
IX(P1) = IW(J)
END IF
END DO
DO J = N, P1OLD, -1
IF ( BTEST(IW(J), ILIM-1) ) THEN
P0 = P0 + 1
IX(P0) = IW(J)
ELSE
P1 = P1 - 1
IX(P1) = IW(J)
END IF
END DO
*
### =================================================================
* Reverse the order of the greater value partition
*
### =================================================================
P1OLD = P1
DO J = N, (P1OLD+N)/2+1, -1
SWAP = IX(J)
IX(J) = IX(P1)
IX(P1) = SWAP
P1 = P1 + 1
END DO
RETURN
END ! of RSORT
***********************************************************************
* test program
***********************************************************************
PROGRAM t_sort
IMPLICIT NONE
INTEGER I, N
PARAMETER (N = 11)
INTEGER IX(N), IW(N)
LOGICAL OK
DATA IX / 2, 24, 45, 0, 66, 75, 170, -802, -90, 1066, 666 /
PRINT *, 'before: ', IX
CALL RSORT (IX, IW, N)
PRINT *, 'after: ', IX
* compare
OK = .TRUE.
DO I = 1, N-1
IF (IX(I) > IX(I+1)) OK = .FALSE.
END DO
IF (OK) THEN
PRINT *, 't_sort: successful test'
ELSE
PRINT *, 't_sort: failure!'
END IF
END ! of test program
{{out}}
before: 2 24 45 0 66 75 170 -802 -90 1066 666
after: -802 -90 0 2 24 45 66 75 170 666 1066
t_sort: successful test
Go
LSD radix 256, negatives handled by flipping the high bit.
package main import ( "bytes" "encoding/binary" "fmt" ) // declarations for word size of data type word int32 const wordLen = 4 const highBit = -1 << 31 var data = []word{170, 45, 75, -90, -802, 24, 2, 66} func main() { buf := bytes.NewBuffer(nil) ds := make([][]byte, len(data)) for i, x := range data { binary.Write(buf, binary.LittleEndian, x^highBit) b := make([]byte, wordLen) buf.Read(b) ds[i] = b } bins := make([][][]byte, 256) for i := 0; i < wordLen; i++ { for _, b := range ds { bins[b[i]] = append(bins[b[i]], b) } j := 0 for k, bs := range bins { copy(ds[j:], bs) j += len(bs) bins[k] = bs[:0] } } fmt.Println("original:", data) var w word for i, b := range ds { buf.Write(b) binary.Read(buf, binary.LittleEndian, &w) data[i] = w^highBit } fmt.Println("sorted: ", data) }
Output:
original: [170 45 75 -90 -802 24 2 66]
sorted: [-802 -90 2 24 45 66 75 170]
Groovy
This solution assumes the radix is a power of 2:
def radixSort = { final radixExponent, list -> def fromBuckets = new TreeMap([0:list]) def toBuckets = new TreeMap() final radix = 2**radixExponent final mask = radix - 1 final radixDigitSize = (int)Math.ceil(64/radixExponent) final digitWidth = radixExponent (0..<radixDigitSize).each { radixDigit -> fromBuckets.values().findAll { it != null }.flatten().each { print '.' long bucketNumber = (long)((((long)it) >>> digitWidth*radixDigit) & mask) toBuckets[bucketNumber] = toBuckets[bucketNumber] ?: [] toBuckets[bucketNumber] << it } (fromBuckets, toBuckets) = [toBuckets, fromBuckets] toBuckets.clear() } final overflow = 2**(63 % radixExponent) final pos = {it < overflow} final neg = {it >= overflow} final keys = fromBuckets.keySet() final twosComplIndx = [] + (keys.findAll(neg)) + (keys.findAll(pos)) twosComplIndx.collect { fromBuckets[it] }.findAll { it != null }.flatten() }
Test:
println (radixSort(3, [23,76,99,58,97,57,35,89,51,38,95,92,24,46,31,24,14,12,57,78,4])) println (radixSort(3, [88,18,31,44,4,0,8,81,14,78,20,76,84,33,73,75,82,5,62,70,12,7,1])) println (radixSort(3, [23,-76,-990,580,97,57,350000,Long.MAX_VALUE,89,Long.MIN_VALUE,51,38,95*2**48,92,-24*2**48,46,31*2**32,24,14,12,57,78,4])) println () println (radixSort(8, [23,76,99,58,97,57,35,89,51,38,95,92,24,46,31,24,14,12,57,78,4])) println (radixSort(8, [88,18,31,44,4,0,8,81,14,78,20,76,84,33,73,75,82,5,62,70,12,7,1])) println (radixSort(8, [23,-76,-990,580,97,57,350000,Long.MAX_VALUE,89,Long.MIN_VALUE,51,38,95*2**48,92,-24*2**48,46,31*2**32,24,14,12,57,78,4])) println () println (radixSort(11, [23,76,99,58,97,57,35,89,51,38,95,92,24,46,31,24,14,12,57,78,4])) println (radixSort(11, [88,18,31,44,4,0,8,81,14,78,20,76,84,33,73,75,82,5,62,70,12,7,1])) println (radixSort(11, [23,-76,-990,580,97,57,350000,Long.MAX_VALUE,89,Long.MIN_VALUE,51,38,95*2**48,92,-24*2**48,46,31*2**32,24,14,12,57,78,4])) println () println (radixSort(16, [23,76,99,58,97,57,35,89,51,38,95,92,24,46,31,24,14,12,57,78,4])) println (radixSort(16, [88,18,31,44,4,0,8,81,14,78,20,76,84,33,73,75,82,5,62,70,12,7,1])) println (radixSort(16, [23,-76,-990,580,97,57,350000,Long.MAX_VALUE,89,Long.MIN_VALUE,51,38,95*2**48,92,-24*2**48,46,31*2**32,24,14,12,57,78,4])) println () println (radixSort(32, [23,76,99,58,97,57,35,89,51,38,95,92,24,46,31,24,14,12,57,78,4])) println (radixSort(32, [88,18,31,44,4,0,8,81,14,78,20,76,84,33,73,75,82,5,62,70,12,7,1])) println (radixSort(32, [23,-76,-990,580,97,57,350000,Long.MAX_VALUE,89,Long.MIN_VALUE,51,38,95*2**48,92,-24*2**48,46,31*2**32,24,14,12,57,78,4]))
Output:
..............................................................................................................................................................................................................................................................................................................................................................................................................................................................................[4, 12, 14, 23, 24, 24, 31, 35, 38, 46, 51, 57, 57, 58, 76, 78, 89, 92, 95, 97, 99] ..........................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................[0, 1, 4, 5, 7, 8, 12, 14, 18, 20, 31, 33, 44, 62, 70, 73, 75, 76, 78, 81, 82, 84, 88] ..........................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................[-9223372036854775808, -6755399441055744, -990, -76, 4, 12, 14, 23, 24, 38, 46, 51, 57, 57, 78, 89, 92, 97, 580, 350000, 133143986176, 26740122787512320, 9223372036854775807] ........................................................................................................................................................................[4, 12, 14, 23, 24, 24, 31, 35, 38, 46, 51, 57, 57, 58, 76, 78, 89, 92, 95, 97, 99] ........................................................................................................................................................................................[0, 1, 4, 5, 7, 8, 12, 14, 18, 20, 31, 33, 44, 62, 70, 73, 75, 76, 78, 81, 82, 84, 88] ........................................................................................................................................................................................[-9223372036854775808, -6755399441055744, -990, -76, 4, 12, 14, 23, 24, 38, 46, 51, 57, 57, 78, 89, 92, 97, 580, 350000, 133143986176, 26740122787512320, 9223372036854775807] ..............................................................................................................................[4, 12, 14, 23, 24, 24, 31, 35, 38, 46, 51, 57, 57, 58, 76, 78, 89, 92, 95, 97, 99] ..........................................................................................................................................[0, 1, 4, 5, 7, 8, 12, 14, 18, 20, 31, 33, 44, 62, 70, 73, 75, 76, 78, 81, 82, 84, 88] ..........................................................................................................................................[-9223372036854775808, -6755399441055744, -990, -76, 4, 12, 14, 23, 24, 38, 46, 51, 57, 57, 78, 89, 92, 97, 580, 350000, 133143986176, 26740122787512320, 9223372036854775807] ....................................................................................[4, 12, 14, 23, 24, 24, 31, 35, 38, 46, 51, 57, 57, 58, 76, 78, 89, 92, 95, 97, 99] ............................................................................................[0, 1, 4, 5, 7, 8, 12, 14, 18, 20, 31, 33, 44, 62, 70, 73, 75, 76, 78, 81, 82, 84, 88] ............................................................................................[-9223372036854775808, -6755399441055744, -990, -76, 4, 12, 14, 23, 24, 38, 46, 51, 57, 57, 78, 89, 92, 97, 580, 350000, 133143986176, 26740122787512320, 9223372036854775807] ..........................................[4, 12, 14, 23, 24, 24, 31, 35, 38, 46, 51, 57, 57, 58, 76, 78, 89, 92, 95, 97, 99] ..............................................[0, 1, 4, 5, 7, 8, 12, 14, 18, 20, 31, 33, 44, 62, 70, 73, 75, 76, 78, 81, 82, 84, 88] ..............................................[-9223372036854775808, -6755399441055744, -990, -76, 4, 12, 14, 23, 24, 38, 46, 51, 57, 57, 78, 89, 92, 97, 580, 350000, 133143986176, 26740122787512320, 9223372036854775807] ``` ## Haskell ```haskell import Data.Bits (Bits(testBit, bitSize)) import Data.List (partition) lsdSort :: (Ord a, Bits a) => [a] -> [a] lsdSort = fixSort positiveLsdSort msdSort :: (Ord a, Bits a) => [a] -> [a] msdSort = fixSort positiveMsdSort -- Fix a sort that puts negative numbers at the end, like positiveLsdSort and positiveMsdSort fixSort sorter list = uncurry (flip (++)) (break (< 0) (sorter list)) positiveLsdSort :: (Bits a) => [a] -> [a] positiveLsdSort list = foldl step list [0..bitSize (head list)] where step list bit = uncurry (++) (partition (not . flip testBit bit) list) positiveMsdSort :: (Bits a) => [a] -> [a] positiveMsdSort list = aux (bitSize (head list) - 1) list where aux _ [] = [] aux (-1) list = list aux bit list = aux (bit - 1) lower ++ aux (bit - 1) upper where (lower, upper) = partition (not . flip testBit bit) list ``` =={{header|Icon}} and {{header|Unicon}}== The following is nice and short and works in both languages. However it contains a subtle inefficiency: subscripting a numeric value first coerces it into a string. ```unicon procedure main(A) every writes((!rSort(A)||" ")|"\n") end procedure rSort(A) every (min := A[1]) >:= !A every (mlen := *(A[1]-min)) <:= (!A - min) every i := !*mlen do { every put(b := [], |[]\12) every a := !A do put(b[(a-min)[-i]+2|1], a) every put(A := [],!!b) } return A end ``` Sample run: ```txt ->radix 31 123 -98 7090 802 2 -98 2 31 123 802 7090 -> ``` ## J {{eff note|J|/:~}}keys f/. data
evaluates the function f on each group of data at the same position as similar keys. Sorting requires ordered keys. This code uses a J idiom: prepend the keys and matching data. The extra data is removed by behead}.
. ```j radixSortR =: 3 : 0 NB. base radixSort data 16 radixSortR y : keys =. x #.^:_1 y NB. compute keys length =. #{.keys extra =. (-length) {."0 buckets =. i.x for_pass. i.-length do. keys =. ; (buckets,pass{"1 keys) <@:}./.extra,keys end. x#.keys NB. restore the data ) ``` An alternate implementation is ```j radixsort=: (] #~ [: +/ =/) i.@(>./) ``` This uses the maximum value of the list for the base, which allows the list to be sorted in one pass. Example use: ```j radixsort ?.@#~10 4 5 6 6 6 6 6 8 8 ``` Or, for negative number support: ```j rsort=: (] + radixsort@:-) <./ ``` Example: ```j rsort _6+?.@#~10 _2 _1 0 0 0 0 0 2 2 ``` ## Java ```java public static int[] sort(int[] old) { // Loop for every bit in the integers for (int shift = Integer.SIZE - 1; shift > -1; shift--) { // The array to put the partially sorted array into int[] tmp = new int[old.length]; // The number of 0s int j = 0; // Move the 0s to the new array, and the 1s to the old one for (int i = 0; i < old.length; i++) { // If there is a 1 in the bit we are testing, the number will be negative boolean move = old[i] << shift >= 0; // If this is the last bit, negative numbers are actually lower if (shift == 0 ? !move : move) { tmp[j] = old[i]; j++; } else { // It's a 1, so stick it in the old array for now old[i - j] = old[i]; } } // Copy over the 1s from the old array for (int i = j; i < tmp.length; i++) { tmp[i] = old[i - j]; } // And now the tmp array gets switched for another round of sorting old = tmp; } return old; } ``` {{trans|NetRexx}} ```Java import java.util.ArrayList; import java.util.Arrays; import java.util.LinkedList; import java.util.List; import java.util.Queue; public class RSortingRadixsort00 { public RSortingRadixsort00() { return; } public static int[] lsdRadixSort(int[] tlist) { Listintermediates; int[] limits = getLimits(tlist); tlist = rescale(tlist, limits[1]); for (int px = 1; px <= limits[2]; ++px) { @SuppressWarnings("unchecked") Queue bukits[] = new Queue[10]; for (int ix = 0; ix < tlist.length; ++ix) { int cval = tlist[ix]; int digit = (int) (cval / Math.pow(10, px - 1) % 10); if (bukits[digit] == null) { bukits[digit] = new LinkedList<>(); } bukits[digit].add(cval); } intermediates = new ArrayList<>(); for (int bi = 0; bi < 10; ++bi) { if (bukits[bi] != null) { while (bukits[bi].size() > 0) { int nextd; nextd = bukits[bi].poll(); intermediates.add(nextd); } } } for (int iw = 0; iw < intermediates.size(); ++iw) { tlist[iw] = intermediates.get(iw); } } tlist = rescale(tlist, -limits[1]); return tlist; } private static int[] rescale(int[] arry, int delta) { for (int ix = 0; ix < arry.length; ++ix) { arry[ix] -= delta; } return arry; } private static int[] getLimits(int[] tlist) { int[] lims = new int[3]; for (int i_ = 0; i_ < tlist.length; ++i_) { lims[0] = Math.max(lims[0], tlist[i_]); lims[1] = Math.min(lims[1], tlist[i_]); } lims[2] = (int) Math.ceil(Math.log10(lims[0] - lims[1])); return lims; } private static void runSample(String[] args) { int[][] lists = { new int[] { 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0, -0, -1, -2, -3, -4, -5, -6, -7, -8, -9, -10, }, new int[] { -10, -9, -8, -7, -6, -5, -4, -3, -2, -1, -0, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, }, new int[] { 2, 24, 45, 0, 66, 75, 170, -802, -90, 1066, 666, }, new int[] { 170, 45, 75, 90, 2, 24, 802, 66, }, new int[] { -170, -45, -75, -90, -2, -24, -802, -66, }, }; long etime; lsdRadixSort(Arrays.copyOf(lists[0], lists[0].length)); // do one pass to set up environment to remove it from timings for (int[] tlist : lists) { System.out.println(array2list(tlist)); etime = System.nanoTime(); tlist = lsdRadixSort(tlist); etime = System.nanoTime() - etime; System.out.println(array2list(tlist)); System.out.printf("Elapsed time: %fs%n", ((double) etime / 1_000_000_000.0)); System.out.println(); } return; } private static List array2list(int[] arry) { List target = new ArrayList<>(arry.length); for (Integer iv : arry) { target.add(iv); } return target; } public static void main(String[] args) { runSample(args); return; } } ``` {{out}} ```txt [10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0, 0, -1, -2, -3, -4, -5, -6, -7, -8, -9, -10] [-10, -9, -8, -7, -6, -5, -4, -3, -2, -1, 0, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10] Elapsed time: 0.000256s [-10, -9, -8, -7, -6, -5, -4, -3, -2, -1, 0, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10] [-10, -9, -8, -7, -6, -5, -4, -3, -2, -1, 0, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10] Elapsed time: 0.000198s [2, 24, 45, 0, 66, 75, 170, -802, -90, 1066, 666] [-802, -90, 0, 2, 24, 45, 66, 75, 170, 666, 1066] Elapsed time: 0.000187s [170, 45, 75, 90, 2, 24, 802, 66] [2, 24, 45, 66, 75, 90, 170, 802] Elapsed time: 0.000088s [-170, -45, -75, -90, -2, -24, -802, -66] [-802, -170, -90, -75, -66, -45, -24, -2] Elapsed time: 0.000113s ``` ## jq ```jq # Sort the input array; # "base" must be an integer greater than 1 def radix_sort(base): # We only need the ceiling of non-negatives: def ceil: if . == floor then . else (. + 1 | floor) end; min as $min | map(. - $min) | ((( max|log) / (base|log)) | ceil) as $rounds | reduce range(0; $rounds) as $i # state: [ base^i, buckets ] ( [1, .]; .[0] as $base_i | reduce .[1][] as $n ([]; (($n/$base_i) % base) as $digit | .[$digit] += [$n] ) | [($base_i * base), (map(select(. != null)) | flatten)] ) | .[1] | map(. + $min) ; def radix_sort: radix_sort(10); ``` '''Example''' ```jq # Verify that radix_sort agrees with sort ( [1, 3, 8, 9, 0, 0, 8, 7, 1, 6], [170, 45, 75, 90, 2, 24, 802, 66], [170, 45, 75, 90, 2, 24, -802, -66] ) | (radix_sort == sort) ``` {{Out}} true true true ## Julia {{trans|Scala}} ```julia function radixsort(tobesorted::Vector{Int64}) arr = deepcopy(tobesorted) for shift in 63:-1:0 tmp = Vector{Int64}(undef, length(arr)) j = 0 for i in 1:length(arr) if (shift == 0) == ((arr[i] << shift) >= 0) arr[i - j] = arr[i] else tmp[j + 1] = arr[i] j += 1 end end tmp[j+1:end] .= arr[1:length(tmp)-j] arr = tmp end arr end function testradixsort() arrays = [[170, 45, 75, -90, -802, 24, 2, 66], [-4, 5, -26, 58, -990, 331, 331, 990, -1837, 2028]] for array in arrays println(radixsort(array)) end end testradixsort() ``` {{output}} ```txt [-802, -90, 2, 24, 45, 66, 75, 170] [-1837, -990, -26, -4, 5, 58, 331, 331, 990, 2028] ``` ## Kotlin {{trans|Java}} ```scala // version 1.1.2 fun radixSort(original: IntArray): IntArray { var old = original // Need this to be mutable // Loop for every bit in the integers for (shift in 31 downTo 0) { val tmp = IntArray(old.size) // The array to put the partially sorted array into var j = 0 // The number of 0s // Move the 0s to the new array, and the 1s to the old one for (i in 0 until old.size) { // If there is a 1 in the bit we are testing, the number will be negative val move = (old[i] shl shift) >= 0 // If this is the last bit, negative numbers are actually lower val toBeMoved = if (shift == 0) !move else move if (toBeMoved) tmp[j++] = old[i] else { // It's a 1, so stick it in the old array for now old[i - j] = old[i] } } // Copy over the 1s from the old array for (i in j until tmp.size) tmp[i] = old[i - j] // And now the tmp array gets switched for another round of sorting old = tmp } return old } fun main(args: Array ) { val arrays = arrayOf( intArrayOf(170, 45, 75, -90, -802, 24, 2, 66), intArrayOf(-4, 5, -26, 58, -990, 331, 331, 990, -1837, 2028) ) for (array in arrays) println(radixSort(array).contentToString()) } ``` {{out}} ```txt [-802, -90, 2, 24, 45, 66, 75, 170] [-1837, -990, -26, -4, 5, 58, 331, 331, 990, 2028] ``` ## Mathematica ```Mathematica ClearAll[SortByPos, RadixSort] SortByPos[data : {_List ..}, pos_Integer] := Module[{digs, order}, digs = data[[All, pos]]; order = Ordering[digs]; data[[order]] ] RadixSort[x : {_Integer ..}] := Module[{y, digs, maxlen, offset}, offset = Min[x]; y = x - offset; digs = IntegerDigits /@ y; maxlen = Max[Length /@ digs]; digs = IntegerDigits[#, 10, maxlen] & /@ y; digs = Fold[SortByPos, digs, -Range[maxlen]]; digs = FromDigits /@ digs; digs += offset; digs ] ``` Testing out the algorithm: ```Mathematica RadixSort[{170,45,75,-90,-802,24,2,66}] RadixSort[{170,45,75,90,802,2,24,66}] ``` {{out}} ```txt {-802,-90,2,24,45,66,75,170} {2,24,45,66,75,90,170,802} ``` ## NetRexx Uses a suggestion in the discussion page to handle negative values.
Limitations - Handles decimal digits only. ### Using the Rexx class ```NetRexx /* NetRexx */ options replace format comments java crossref symbols nobinary runSample(arg) return -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ method radixSort(tlist = Rexx[]) public static returns Rexx[] -- scale the array to start at zero to allow handling of -ve values parse getLimits(tlist) maxn minn maxl . tlist = rescale(tlist, minn) loop px = maxl to 1 by -1 bukits = '' loop ix = 0 to tlist.length - 1 cval = tlist[ix].right(maxl, 0) parse cval . =(px) digit +1 . bukits[digit] = bukits[digit] (cval + 0) -- simulates a stack end ix intermediates = '' loop bi = 0 to 9 intermediates = intermediates bukits[bi] -- sumulates unstack end bi -- reload array loop iw = 1 to intermediates.words() tlist[iw - 1] = intermediates.word(iw) end iw end px -- restore the array to original scale tlist = rescale(tlist, -minn) return tlist -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ method rescale(arry = Rexx[], newbase) private static returns Rexx[] loop ix = 0 to arry.length - 1 arry[ix] = arry[ix] - newbase end ix return arry -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ method getLimits(arry = Rexx[]) private static returns Rexx maxn = 0 minn = 0 maxl = 0 loop i_ = 0 to arry.length - 1 maxn = maxn.max(arry[i_]) minn = minn.min(arry[i_]) end i_ maxl = (maxn - minn).length() return maxn minn maxl -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ method runSample(arg) private static lists = [- [2, 24, 45, 0, 66, 75, 170, -802, -90, 1066, 666], - [170, 45, 75, 90, 2, 24, 802, 66], - [10, 9, 8, 7, 8, 5, 4, 3, 2, 1, 0], - [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10], - [-10, -9, -8, -7, -8, -5, -4, -3, -2, -1, -0], - [-0, -1, -2, -3, -4, -5, -6, -7, -8, -9, -10], - [-10, -19, -18, -17, -18, -15, -14, -13, -12, -11, -100], - [10, 9, 8, 7, 8, 5, 4, 3, 2, 1, 0, -0, -1, -2, -3, -4, -5, -6, -7, -8, -9, -10], - [-10, -9, -8, -7, -8, -5, -4, -3, -2, -1, -0, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10] - ] loop il = 0 to lists.length - 1 tlist = lists[il] say ' Input:' Arrays.asList(tlist) say 'Output:' Arrays.asList(radixSort(tlist)) say end il return ``` {{out}} ```txt Input: [2, 24, 45, 0, 66, 75, 170, -802, -90, 1066, 666] Output: [-802, -90, 0, 2, 24, 45, 66, 75, 170, 666, 1066] Input: [170, 45, 75, 90, 2, 24, 802, 66] Output: [2, 24, 45, 66, 75, 90, 170, 802] Input: [10, 9, 8, 7, 8, 5, 4, 3, 2, 1, 0] Output: [0, 1, 2, 3, 4, 5, 7, 8, 8, 9, 10] Input: [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10] Output: [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10] Input: [-10, -9, -8, -7, -8, -5, -4, -3, -2, -1, 0] Output: [-10, -9, -8, -8, -7, -5, -4, -3, -2, -1, 0] Input: [0, -1, -2, -3, -4, -5, -6, -7, -8, -9, -10] Output: [-10, -9, -8, -7, -6, -5, -4, -3, -2, -1, 0] Input: [-10, -19, -18, -17, -18, -15, -14, -13, -12, -11, -100] Output: [-100, -19, -18, -18, -17, -15, -14, -13, -12, -11, -10] Input: [10, 9, 8, 7, 8, 5, 4, 3, 2, 1, 0, 0, -1, -2, -3, -4, -5, -6, -7, -8, -9, -10] Output: [-10, -9, -8, -7, -6, -5, -4, -3, -2, -1, 0, 0, 1, 2, 3, 4, 5, 7, 8, 8, 9, 10] Input: [-10, -9, -8, -7, -8, -5, -4, -3, -2, -1, 0, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10] Output: [-10, -9, -8, -8, -7, -5, -4, -3, -2, -1, 0, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10] ``` ### Using Collection classes ```NetRexx /* NetRexx */ options replace format comments java crossref symbols nobinary import java.util.Queue runSample(arg) return -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ method radixSort(tlist = Rexx[]) public static returns Rexx[] -- scale the array to start at zero to allow handling of -ve values limits = '' parse '!MAXN !MINN !MAXL' maxn_ minn_ maxl_ . parse getLimits(tlist) maxn minn maxl . limits[maxn_] = maxn limits[minn_] = minn limits[maxl_] = maxl tlist = rescale(tlist, limits[minn_]) loop px = limits[maxl_] to 1 by -1 bukits = Queue[10] -- stacks for digits 0 .. 9 loop ix = 0 while ix < tlist.length cval = tlist[ix].right(limits[maxl_], 0) parse cval . =(px) digit +1 . -- extract next digit (fun with parse) -- alternatively: digit = (cval % (10 ** (px - 1))) // 10 if bukits[digit] == null then bukits[digit] = LinkedList() bukits[digit].add((cval + 0)) end ix intermediates = ArrayList() loop bi = 0 to 9 if bukits[bi] \= null then loop while bukits[bi].size() > 0 nextd = bukits[bi].poll() intermediates.add(nextd) end end bi -- reload result array loop iw = 0 while iw < intermediates.size() tlist[iw] = Rexx intermediates.get(iw) end iw end px -- restore the array to original scale tlist = rescale(tlist, -limits[minn_]) return tlist -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ method rescale(arry = Rexx[], newbase) private static returns Rexx[] loop ix = 0 to arry.length - 1 arry[ix] = arry[ix] - newbase end ix return arry -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ method getLimits(arry = Rexx[]) private static returns Rexx maxn = 0 minn = 0 maxl = 0 loop i_ = 0 to arry.length - 1 maxn = maxn.max(arry[i_]) minn = minn.min(arry[i_]) end i_ maxl = (maxn - minn).length() return maxn minn maxl -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ method runSample(arg) private static lists = [- [2, 24, 45, 0, 66, 75, 170, -802, -90, 1066, 666], - [170, 45, 75, 90, 2, 24, 802, 66], - [10, 9, 8, 7, 8, 5, 4, 3, 2, 1, 0], - [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10], - [-10, -9, -8, -7, -8, -5, -4, -3, -2, -1, -0], - [-0, -1, -2, -3, -4, -5, -6, -7, -8, -9, -10], - [-10, -19, -18, -17, -18, -15, -14, -13, -12, -11, -100], - [10, 9, 8, 7, 8, 5, 4, 3, 2, 1, 0, -0, -1, -2, -3, -4, -5, -6, -7, -8, -9, -10], - [-10, -9, -8, -7, -8, -5, -4, -3, -2, -1, -0, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10] - ] loop il = 0 to lists.length - 1 tlist = lists[il] say ' Input:' Arrays.asList(tlist) say 'Output:' Arrays.asList(radixSort(tlist)) say end il return ``` ## Perl Radix sort in base 10. ```perl #!/usr/bin/perl use warnings; use strict; sub radix { my @tab = ([@_]); my $max_length = 0; length > $max_length and $max_length = length for @_; $_ = sprintf "%0${max_length}d", $_ for @{ $tab[0] }; # Add zeros. for my $pos (reverse -$max_length .. -1) { my @newtab; for my $bucket (@tab) { for my $n (@$bucket) { my $char = substr $n, $pos, 1; $char = -1 if '-' eq $char; $char++; push @{ $newtab[$char] }, $n; } } @tab = @newtab; } my @return; my $negative = shift @tab; # Negative bucket must be reversed. push @return, reverse @$negative; for my $bucket (@tab) { push @return, @{ $bucket // [] }; } $_ = 0 + $_ for @return; # Remove zeros. return @return; } ``` To test, add the following lines: ```perl>use Test::More tests = 1000; for (1 .. 1000) { my @l = map int rand(2000) - 1000, 0 .. 20; is_deeply([radix(@l)], [sort { $a <=> $b } @l]); } ``` ## Perl 6 A base-10 radix sort, done on the string representation of the integers. Signs are handled by in-place reversal of the '-' bucket on the last iteration. (The sort in there is not cheating; it only makes sure we process the buckets in the right order, since classify might return the buckets in random order. It might be more efficient to create our own ordered buckets, but this is succinct.) ```perl6 sub radsort (@ints) { my $maxlen = max @ints».chars; my @list = @ints».fmt("\%0{$maxlen}d"); for reverse ^$maxlen -> $r { my @buckets = @list.classify( *.substr($r,1) ).sort: *.key; @buckets[0].value = @buckets[0].value.reverse.List if !$r and @buckets[0].key eq '-'; @list = flat map *.value.values, @buckets; } @list».Int; } .say for radsort (-2_000 .. 2_000).roll(20); ``` {{out}} ```txt -1585 -1427 -1228 -1067 -945 -657 -643 -232 -179 -28 37 411 488 509 716 724 1504 1801 1864 1939 ``` ## Phix ```Phix function radixSortn(sequence s, integer n) sequence buckets = repeat({},10) sequence res = {} for i=1 to length(s) do integer digit = remainder(floor(s[i]/power(10,n-1)),10)+1 buckets[digit] = append(buckets[digit],s[i]) end for for i=1 to length(buckets) do integer len = length(buckets[i]) if len!=0 then if len=1 or n=1 then res &= buckets[i] else res &= radixSortn(buckets[i],n-1) end if end if end for return res end function function split_by_sign(sequence s) sequence buckets = {{},{}} for i=1 to length(s) do integer si = s[i] if si<0 then buckets[1] = append(buckets[1],-si) else buckets[2] = append(buckets[2],si) end if end for return buckets end function function radixSort(sequence s) integer mins = min(s) integer passes = max(max(s),abs(mins)) passes = floor(log10(passes))+1 if mins<0 then sequence buckets = split_by_sign(s) buckets[1] = reverse(sq_uminus(radixSortn(buckets[1],passes))) buckets[2] = radixSortn(buckets[2],passes) s = buckets[1]&buckets[2] else s = radixSortn(s,passes) end if return s end function ?radixSort({1, 3, 8, 9, 0, 0, 8, 7, 1, 6}) ?radixSort({170, 45, 75, 90, 2, 24, 802, 66}) ?radixSort({170, 45, 75, 90, 2, 24, -802, -66}) ?radixSort({100000, -10000, 400, 23, 10000}) ``` {{out}} ```txt {0,0,1,1,3,6,7,8,8,9} {2,24,45,66,75,90,170,802} {-802,-66,2,24,45,75,90,170} {-10000,23,400,10000,100000} ``` ## PicoLisp This is a LSD base-2 radix sort using queues: ```PicoLisp (de radixSort (Lst) (let Mask 1 (while (let (Pos (list NIL NIL) Neg (list NIL NIL) Flg) (for N Lst (queue (if2 (ge0 N) (bit? Mask N) (cdr Pos) Pos Neg (cdr Neg) ) N ) (and (>= (abs N) Mask) (on Flg)) ) (setq Lst (conc (apply conc Neg) (apply conc Pos)) Mask (* 2 Mask) ) Flg ) ) ) Lst ) ``` Output: ```txt : (radixSort (make (do 12 (link (rand -999 999))))) -> (-999 -930 -666 -336 -218 68 79 187 391 405 697 922) ``` ## PureBasic ```PureBasic Structure bucket List i.i() EndStructure DataSection ;sets specify the size (1 based) followed by each integer set1: Data.i 10 ;size Data.i 1, 3, 8, 9, 0, 0, 8, 7, 1, 6 ;data set2: Data.i 8 Data.i 170, 45, 75, 90, 2, 24, 802, 66 set3: Data.i 8 Data.i 170, 45, 75, 90, 2, 24, -802, -66 EndDataSection Procedure setIntegerArray(Array x(1), *setPtr) Protected i, count count = PeekI(*setPtr) - 1 ;convert to zero based count *setPtr + SizeOf(Integer) ;move pointer forward to data Dim x(count) For i = 0 To count x(i) = PeekI(*setPtr + i * SizeOf(Integer)) Next EndProcedure Procedure displayArray(Array x(1)) Protected i, Size = ArraySize(x()) For i = 0 To Size Print(Str(x(i))) If i < Size: Print(", "): EndIf Next PrintN("") EndProcedure Procedure radixSort(Array x(1), Base = 10) Protected count = ArraySize(x()) If Base < 1 Or count < 1: ProcedureReturn: EndIf ;exit due to invalid values Protected i, pv, digit, digitCount, maxAbs, pass, index ;find element with largest number of digits For i = 0 To count If Abs(x(i)) > maxAbs maxAbs = Abs(x(i)) EndIf Next digitCount = Int(Log(maxAbs)/Log(Base)) + 1 For pass = 1 To digitCount Dim sortBuckets.bucket(Base * 2 - 1) pv = Pow(Base, pass - 1) ;place elements in buckets according to the current place-value's digit For index = 0 To count digit = Int(x(index)/pv) % Base + Base AddElement(sortBuckets(digit)\i()) sortBuckets(digit)\i() = x(index) Next ;transfer contents of buckets back into array index = 0 For digit = 1 To (Base * 2) - 1 ForEach sortBuckets(digit)\i() x(index) = sortBuckets(digit)\i() index + 1 Next Next Next EndProcedure If OpenConsole() Dim x(0) setIntegerArray(x(), ?set1) radixSort(x()): displayArray(x()) setIntegerArray(x(), ?set2) radixSort(x()): displayArray(x()) setIntegerArray(x(), ?set3) radixSort(x(), 2): displayArray(x()) Print(#CRLF$ + #CRLF$ + "Press ENTER to exit"): Input() CloseConsole() EndIf ``` Sample output: ```txt 0, 0, 1, 1, 3, 6, 7, 8, 8, 9 2, 24, 45, 66, 75, 90, 170, 802 -802, -66, 2, 24, 45, 75, 90, 170 ``` ## Python {{works with|Python|2.6}} This is the Wikipedia example code extended with an extra pass to sort negative values correctly. ```python #python2.6 < from math import log def getDigit(num, base, digit_num): # pulls the selected digit return (num // base ** digit_num) % base def makeBlanks(size): # create a list of empty lists to hold the split by digit return [ [] for i in range(size) ] def split(a_list, base, digit_num): buckets = makeBlanks(base) for num in a_list: # append the number to the list selected by the digit buckets[getDigit(num, base, digit_num)].append(num) return buckets # concatenate the lists back in order for the next step def merge(a_list): new_list = [] for sublist in a_list: new_list.extend(sublist) return new_list def maxAbs(a_list): # largest abs value element of a list return max(abs(num) for num in a_list) def split_by_sign(a_list): # splits values by sign - negative values go to the first bucket, # non-negative ones into the second buckets = [[], []] for num in a_list: if num < 0: buckets[0].append(num) else: buckets[1].append(num) return buckets def radixSort(a_list, base): # there are as many passes as there are digits in the longest number passes = int(round(log(maxAbs(a_list), base)) + 1) new_list = list(a_list) for digit_num in range(passes): new_list = merge(split(new_list, base, digit_num)) return merge(split_by_sign(new_list)) ``` An alternate implementation using which works on Python 3: ```python #python3.7 < def flatten(some_list): """ Flatten a list of lists. Usage: flatten([[list a], [list b], ...]) Output: [elements of list a, elements of list b] """ new_list = [] for sub_list in some_list: new_list += sub_list return new_list def radix(some_list, idex=None, size=None): """ Recursive radix sort Usage: radix([unsorted list]) Output: [sorted list] """ # Initialize variables not set in the initial call if size == None: largest_num = max(some_list) largest_num_str = str(largest_num) largest_num_len = len(largest_num_str) size = largest_num_len if idex == None: idex = size # Translate the index we're looking at into an array index. # e.g., looking at the 10's place for 100: # size: 3 # idex: 2 # i: (3-2) == 1 # str(123)[i] -> 2 i = size - idex # The recursive base case. # Hint: out of range indexing errors if i >= size: return some_list # Initialize the bins we will place numbers into bins = [[] for _ in range(10)] # Iterate over the list of numbers we are given for e in some_list: # The destination bin; e.g.,: # size: 5 # e: 29 # num_s: '00029' # i: 3 # dest_c: '2' # dest_i: 2 num_s = str(e).zfill(size) dest_c = num_s[i] dest_i = int(dest_c) bins[dest_i] += [e] result = [] for b in bins: # Make the recursive call # Sort each of the sub-lists in our bins result.append(radix(b, idex-1, size)) # Flatten our list # This is also called in our recursive call, # so we don't need flatten to be recursive. flattened_result = flatten(result) return flattened_result ``` That same example but more compact: ```python #python3.7 < def flatten(l): return [y for x in l for y in x] def radix(l, p=None, s=None): if s == None: s = len(str(max(l))) if p == None: p = s i = s - p if i >= s: return l bins = [[] for _ in range(10)] for e in l: bins[int(str(e).zfill(s)[i])] += [e] return flatten([radix(b, p-1, s) for b in bins] ``` ## QB64 ```QB64 #lang QB64 '* don't be an a$$. Keep this credit notice with the source: '* written/refactored by CodeGuy, 2018. '* also works with negative numbers. TESTN& = 63 A$ = "" REDIM b(0 TO TESTN&) AS DOUBLE FOR s& = -1 TO 1 STEP 2 A$ = A$ + CHR$(13) + CHR$(10) + "Random order:" FOR i = 0 TO TESTN& b(i) = (1000 * RND) AND 1023 IF i MOD 2 THEN b(i) = -b(i) IF i < TESTN& THEN A$ = A$ + LTRIM$(STR$(b(i))) + "," ELSE A$ = A$ + LTRIM$(STR$(b(i))) + CHR$(13) + CHR$(10) END IF NEXT RadixSort b(), 0, TESTN&, s& IF s& = -1 THEN A$ = A$ + "descending order" + CHR$(13) + CHR$(10) ELSE A$ = A$ + "ascending order" + CHR$(13) + CHR$(10) END IF FOR i = 0 TO TESTN& PRINT b(i); IF i < TESTN& THEN A$ = A$ + LTRIM$(STR$(b(i))) + "," ELSE A$ = A$ + LTRIM$(STR$(b(i))) + CHR$(13) + CHR$(10) END IF NEXT NEXT PRINT A$ TYPE MinMaxRec min AS LONG max AS LONG END TYPE SUB RadixSort (CGSortLibArr() AS DOUBLE, start&, finish&, order&) ArrayIsInteger CGSortLibArr(), start&, finish&, errindex&, errcon& IF errcon& THEN '* use another stable sort and sort anyway MergeSort CGSortLibArr(), start&, finish&, order& ELSE DIM RSMMrec AS MinMaxRec GetMinMaxArray CGSortLibArr(), start&, finish&, RSMMrec IF CGSortLibArr(RSMMrec.min) = CGSortLibArr(RSMMrec.max) THEN EXIT SUB '* no div0 bombs delta# = CGSortLibArr(RSMMrec.max) - CGSortLibArr(RSMMrec.min) DIM pow2 AS _UNSIGNED _INTEGER64 DIM NtmpN AS _UNSIGNED _INTEGER64 DIM Int64MaxShift AS _INTEGER64: Int64MaxShift = 2 ^ 64 REDIM ct&(-1 TO 1) REDIM RadixCGSortLibArr(0 TO 1, finish& - start&) AS DOUBLE SELECT CASE order& CASE 1 pow2 = Int64MaxShift bits& = LEN(Int64MaxShift) * 8 DO UNTIL bits& < 0 FOR i& = start& TO finish& NtmpN = Int64MaxShift * (CGSortLibArr(i&) - CGSortLibArr(RSMMrec.min)) / (delta#) IF NtmpN AND pow2 THEN tmpradix% = 1 ELSE tmpradix% = 0 END IF RadixCGSortLibArr(tmpradix%, ct&(tmpradix%)) = CGSortLibArr(i&) ct&(tmpradix%) = ct&(tmpradix%) + 1 NEXT c& = start& FOR i& = 0 TO 1 FOR j& = 0 TO ct&(i&) - 1 CGSortLibArr(c&) = RadixCGSortLibArr(i&, j&) c& = c& + 1 NEXT ct&(i&) = 0 NEXT pow2 = pow2 / 2 bits& = bits& - 1 LOOP CASE ELSE pow2 = 1 FOR bits& = 0 TO 63 FOR i& = start& TO finish& NtmpN = Int64MaxShift * (CGSortLibArr(i&) - CGSortLibArr(RSMMrec.min)) / (delta#) IF NtmpN AND pow2 THEN tmpradix% = 1 ELSE tmpradix% = 0 END IF RadixCGSortLibArr(tmpradix%, ct&(tmpradix%)) = CGSortLibArr(i&) ct&(tmpradix%) = ct&(tmpradix%) + 1 NEXT c& = start& FOR i& = 0 TO 1 FOR j& = 0 TO ct&(i&) - 1 CGSortLibArr(c&) = RadixCGSortLibArr(i&, j&) c& = c& + 1 NEXT ct&(i&) = 0 NEXT pow2 = pow2 * 2 NEXT END SELECT ERASE RadixCGSortLibArr, ct& END IF END SUB SUB ArrayIsInteger (CGSortLibArr() AS DOUBLE, start&, finish&, errorindex&, IsInt&) IsInt& = 1 errorindex& = start& FOR IsIntegerS& = start& TO finish& IF CGSortLibArr(IsIntegerS&) MOD 1 THEN errorindex& = IsIntegerS& IsInt& = 0 EXIT FUNCTION END IF NEXT END FUNCTION SUB MergeSort (CGSortLibArr() AS DOUBLE, start&, finish&, order&) SELECT CASE finish& - start& CASE IS > 31 middle& = start& + (finish& - start&) \ 2 MergeSort CGSortLibArr(), start&, middle&, order& MergeSort CGSortLibArr(), middle& + 1, finish&, order& 'IF order& = 1 THEN EfficientMerge CGSortLibArr(), start&, finish&, order& 'ELSE ' MergeRoutine CGSortLibArr(), start&, finish&, order& 'END IF CASE IS > 0 InsertionSort CGSortLibArr(), start&, finish&, order& END SELECT END SUB SUB EfficientMerge (right() AS DOUBLE, start&, finish&, order&) half& = start& + (finish& - start&) \ 2 REDIM left(start& TO half&) AS DOUBLE '* hold the first half of the array in left() -- must be the same type as right() FOR LoadLeft& = start& TO half& left(LoadLeft&) = right(LoadLeft&) NEXT SELECT CASE order& CASE 1 i& = start& j& = half& + 1 insert& = start& DO IF i& > half& THEN '* left() exhausted IF j& > finish& THEN '* right() exhausted EXIT DO ELSE '* stuff remains in right to be inserted, so flush right() WHILE j& <= finish& right(insert&) = right(j&) j& = j& + 1 insert& = insert& + 1 WEND EXIT DO '* and exit END IF ELSE IF j& > finish& THEN WHILE i& < LoadLeft& right(insert&) = left(i&) i& = i& + 1 insert& = insert& + 1 WEND EXIT DO ELSE IF right(j&) < left(i&) THEN right(insert&) = right(j&) j& = j& + 1 ELSE right(insert&) = left(i&) i& = i& + 1 END IF insert& = insert& + 1 END IF END IF LOOP CASE ELSE i& = start& j& = half& + 1 insert& = start& DO IF i& > half& THEN '* left() exhausted IF j& > finish& THEN '* right() exhausted EXIT DO ELSE '* stuff remains in right to be inserted, so flush right() WHILE j& <= finish& right(insert&) = right(j&) j& = j& + 1 insert& = insert& + 1 WEND EXIT DO '* and exit END IF ELSE IF j& > finish& THEN WHILE i& < LoadLeft& right(insert&) = left(i&) i& = i& + 1 insert& = insert& + 1 WEND EXIT DO ELSE IF right(j&) > left(i&) THEN right(insert&) = right(j&) j& = j& + 1 ELSE right(insert&) = left(i&) i& = i& + 1 END IF insert& = insert& + 1 END IF END IF LOOP END SELECT ERASE left END SUB SUB GetMinMaxArray (CGSortLibArr() AS DOUBLE, Start&, Finish&, GetMinMaxArray_minmax AS MinMaxRec) DIM GetGetMinMaxArray_minmaxArray_i AS LONG DIM GetMinMaxArray_n AS LONG DIM GetMinMaxArray_TT AS LONG DIM GetMinMaxArray_NMod2 AS INTEGER '* this is a workaround for the irritating malfunction '* of MOD using larger numbers and small divisors GetMinMaxArray_n = Finish& - Start& GetMinMaxArray_TT = GetMinMaxArray_n MOD 10000 GetMinMaxArray_NMod2 = GetMinMaxArray_n - 10000 * ((GetMinMaxArray_n - GetMinMaxArray_TT) / 10000) IF (GetMinMaxArray_NMod2 MOD 2) THEN GetMinMaxArray_minmax.min = Start& GetMinMaxArray_minmax.max = Start& GetGetMinMaxArray_minmaxArray_i = Start& + 1 ELSE IF CGSortLibArr(Start&) > CGSortLibArr(Finish&) THEN GetMinMaxArray_minmax.max = Start& GetMinMaxArray_minmax.min = Finish& ELSE GetMinMaxArray_minmax.min = Finish& GetMinMaxArray_minmax.max = Start& END IF GetGetMinMaxArray_minmaxArray_i = Start& + 2 END IF WHILE GetGetMinMaxArray_minmaxArray_i < Finish& IF CGSortLibArr(GetGetMinMaxArray_minmaxArray_i) > CGSortLibArr(GetGetMinMaxArray_minmaxArray_i + 1) THEN IF CGSortLibArr(GetGetMinMaxArray_minmaxArray_i) > CGSortLibArr(GetMinMaxArray_minmax.max) THEN GetMinMaxArray_minmax.max = GetGetMinMaxArray_minmaxArray_i END IF IF CGSortLibArr(GetGetMinMaxArray_minmaxArray_i + 1) < CGSortLibArr(GetMinMaxArray_minmax.min) THEN GetMinMaxArray_minmax.min = GetGetMinMaxArray_minmaxArray_i + 1 END IF ELSE IF CGSortLibArr(GetGetMinMaxArray_minmaxArray_i + 1) > CGSortLibArr(GetMinMaxArray_minmax.max) THEN GetMinMaxArray_minmax.max = GetGetMinMaxArray_minmaxArray_i + 1 END IF IF CGSortLibArr(GetGetMinMaxArray_minmaxArray_i) < CGSortLibArr(GetMinMaxArray_minmax.min) THEN GetMinMaxArray_minmax.min = GetGetMinMaxArray_minmaxArray_i END IF END IF GetGetMinMaxArray_minmaxArray_i = GetGetMinMaxArray_minmaxArray_i + 2 WEND END SUB SUB InsertionSort (CGSortLibArr() AS DOUBLE, start AS LONG, finish AS LONG, order&) DIM InSort_Local_ArrayTemp AS DOUBLE DIM InSort_Local_i AS LONG DIM InSort_Local_j AS LONG SELECT CASE order& CASE 1 FOR InSort_Local_i = start + 1 TO finish InSort_Local_ArrayTemp = CGSortLibArr(InSort_Local_i) InSort_Local_j = InSort_Local_i - 1 DO UNTIL InSort_Local_j < start IF (InSort_Local_ArrayTemp < CGSortLibArr(InSort_Local_j)) THEN CGSortLibArr(InSort_Local_j + 1) = CGSortLibArr(InSort_Local_j) InSort_Local_j = InSort_Local_j - 1 ELSE EXIT DO END IF LOOP CGSortLibArr(InSort_Local_j + 1) = InSort_Local_ArrayTemp NEXT CASE ELSE FOR InSort_Local_i = start + 1 TO finish InSort_Local_ArrayTemp = CGSortLibArr(InSort_Local_i) InSort_Local_j = InSort_Local_i - 1 DO UNTIL InSort_Local_j < start IF (InSort_Local_ArrayTemp > CGSortLibArr(InSort_Local_j)) THEN CGSortLibArr(InSort_Local_j + 1) = CGSortLibArr(InSort_Local_j) InSort_Local_j = InSort_Local_j - 1 ELSE EXIT DO END IF LOOP CGSortLibArr(InSort_Local_j + 1) = InSort_Local_ArrayTemp NEXT END SELECT END SUB ``` ## Racket ```Racket #lang Racket (define (radix-sort l r) (define queues (for/vector #:length r ([_ r]) (make-queue))) (let loop ([l l] [R 1]) (define all-zero? #t) (for ([x (in-list l)]) (define x/R (quotient x R)) (enqueue! (vector-ref queues (modulo x/R r)) x) (unless (zero? x/R) (set! all-zero? #f))) (if all-zero? l (loop (let q-loop ([i 0]) (define q (vector-ref queues i)) (let dq-loop () (if (queue-empty? q) (if (< i (sub1 r)) (q-loop (add1 i)) '()) (cons (dequeue! q) (dq-loop))))) (* R r))))) (for/and ([i 10000]) ; run some tests on random lists with a random radix (define (make-random-list) (for/list ([i (+ 10 (random 10))]) (random 100000))) (define (sorted? l) (match l [(list) #t] [(list x) #t] [(list x y more ...) (and (<= x y) (sorted? (cons y more)))])) (sorted? (radix-sort (make-random-list) (+ 2 (random 98))))) ;; => #t, so all passed ``` ## REXX This REXX version also works with malformed integers. '''7''', '''007''', '''+7''', '''.7e1''', '''7.0''' are all treated as equal. ```rexx /*REXX program performs a radix sort on an integer array (can be negative/zero/positive)*/ call gen /*call subroutine to generate numbers. */ call radSort n /*invoke the radix sort subroutine. */ do j=1 for n; say 'item' right(j, w) "after the radix sort:" right(@.j, w) end /*j*/ /* [↑] display sorted items ───► term.*/ exit /*stick a fork in it, we're all done. */ /*──────────────────────────────────────────────────────────────────────────────────────*/ gen: ILF= 0 2 3 4 5 5 7. 6 6 7 11 7 13 9 8 8 17 8 19 9 10 13 23 9 10 15 , 9 11 29 10 31 10 14 19 12 10 37 21 16 11 41 12 43 15 11 25 47 11 14 12 20 17 , 53 11 16 13 22 31 59 12 61 33 13 12 18 16 67 21 26 14 71 12 73 39 13 23 18 18 , 79 13 12 43 83 14 22 45 32 17 89 13 20 27 34 49 24 13 97 16 17 14 101 , '22 103 19 15 55 107 13 109 18 40 15 113 -42' /*excluding -42, abbreviated above list is called the integer log function*/ n= words(ILF) /* I────── L── F───────*/ w= 0; do m=1 for n; _= word(ILF,m) +0; @.m= _; w= max(w, length(_) ) end /*m*/; return /*W: is the maximum width ↑ of numbers*/ /*──────────────────────────────────────────────────────────────────────────────────────*/ radSort: procedure expose @. w; parse arg size; mote= c2d(' '); #= 1; !.#._n= size !.#._b=1; !.#._i=1; do i=1 for size; [email protected]; @.i= right(abs(y), w, 0); if y<0 then @.i= '-'@.i end /*i*/ /* [↑] negative case.*/ do while #\==0; ctr.=0; L='ffff'x; low=!.#._b; n=!.#._n; $=!.#._i; H= #=#-1 /* [↑] is the radix. */ do j=low for n; parse var @.j =($) _ +1; ctr._=ctr._ + 1 if ctr._==1 & _\=='' then do; if _<>H then H=_ end /* ↑↑ */ end /*j*/ /* └┴─────◄─── << is a strict comparison.*/ _= /* ┌──◄─── >> " " " " */ if L>>H then iterate /*◄─────┘ */ if L==H & ctr._==0 then do; #= #+1; !.#._b= low; !.#._n= n; !.#._i= $+1; iterate end L= c2d(L); H= c2d(H); ?= ctr._ + low; top._= ?; ts= mote max= L do k=L to H; _= d2c(k,1); c= ctr._ /* [↓] swap 2 item radices.*/ if c>ts then parse value c k with ts max; ?= ?+c; top._= ? end /*k*/ piv= low /*set PIVot to the low part of the sort*/ do while piv =c then leave; top._= c; ?= @.c; @.c= it; it= ? end /*forever*/ top._= piv; @.piv=it; piv=piv + ctr._ end /*while piv H then i= L; d= ctr._ if d<=mote then do; if d<2 then iterate; b= top._ do k=b+1 for d-1; q= @.k do j=k-1 by -1 to b while q<<@.j; jp= j+1; @.jp= @.j end /*j*/ jp= j+1; @.jp= q end /*k*/ iterate end #= #+1; !.#._b= top._; !.#._n= d; !.#._i= $ + 1 end /*until i==max*/ end /*while #\==0 */ #= 0 /* [↓↓↓] handle neg. and pos. arrays. */ do i=size by -1 to 1; if @.i>=0 then iterate; #=#+1; @@.#[email protected] end /*i*/ do j=1 for size; if @.j>=0 then do; #= #+1; @@.#= @.j; end; @.j= @@.j+0 end /*j*/; return /* [↑↑↑] combine 2 lists into 1 list. */ ``` {{out|output|text= (with the middle section elided.)}} (Output is shown at '''3/4''' size.) item 1 after the radix sort: -42 item 2 after the radix sort: 0 item 3 after the radix sort: 2 item 4 after the radix sort: 3 item 5 after the radix sort: 4 item 6 after the radix sort: 5 item 7 after the radix sort: 5 item 8 after the radix sort: 6 item 9 after the radix sort: 6 item 10 after the radix sort: 7 item 11 after the radix sort: 7 item 12 after the radix sort: 7 item 13 after the radix sort: 8 . . . (middle section elided.) . . . item 92 after the radix sort: 40 item 93 after the radix sort: 41 item 94 after the radix sort: 43 item 95 after the radix sort: 43 item 96 after the radix sort: 45 item 97 after the radix sort: 47 item 98 after the radix sort: 49 item 99 after the radix sort: 53 item 100 after the radix sort: 55 item 101 after the radix sort: 59 item 102 after the radix sort: 61 item 103 after the radix sort: 67 item 104 after the radix sort: 71 item 105 after the radix sort: 73 item 106 after the radix sort: 79 item 107 after the radix sort: 83 item 108 after the radix sort: 89 item 109 after the radix sort: 97 item 110 after the radix sort: 101 item 111 after the radix sort: 103 item 112 after the radix sort: 107 item 113 after the radix sort: 109 item 114 after the radix sort: 113 ``` ## Ruby Negative number handling courtesy the Tcl solution. ```ruby class Array def radix_sort(base=10) ary = dup rounds = (Math.log(ary.minmax.map(&:abs).max)/Math.log(base)).floor + 1 rounds.times do |i| buckets = Array.new(2*base){[]} base_i = base**i ary.each do |n| digit = (n/base_i) % base digit += base if 0<=n buckets[digit] << n end ary = buckets.flatten p [i, ary] if $DEBUG end ary end def radix_sort!(base=10) replace radix_sort(base) end end p [1, 3, 8, 9, 0, 0, 8, 7, 1, 6].radix_sort p [170, 45, 75, 90, 2, 24, 802, 66].radix_sort p [170, 45, 75, 90, 2, 24, -802, -66].radix_sort p [100000, -10000, 400, 23, 10000].radix_sort ``` running with $DEBUG on produces: ```txt [0, [0, 0, 1, 1, 3, 6, 7, 8, 8, 9]] [0, 0, 1, 1, 3, 6, 7, 8, 8, 9] [0, [170, 90, 2, 802, 24, 45, 75, 66]] [1, [2, 802, 24, 45, 66, 170, 75, 90]] [2, [2, 24, 45, 66, 75, 90, 170, 802]] [2, 24, 45, 66, 75, 90, 170, 802] [0, [-66, -802, 170, 90, 2, 24, 45, 75]] [1, [-66, -802, 2, 24, 45, 170, 75, 90]] [2, [-802, -66, 2, 24, 45, 75, 90, 170]] [-802, -66, 2, 24, 45, 75, 90, 170] [0, [-10000, 100000, 400, 10000, 23]] [1, [-10000, 100000, 400, 10000, 23]] [2, [-10000, 100000, 10000, 23, 400]] [3, [-10000, 100000, 10000, 23, 400]] [4, [-10000, 100000, 23, 400, 10000]] [5, [-10000, 23, 400, 10000, 100000]] [-10000, 23, 400, 10000, 100000] ``` another version (After sorting at the absolute value, it makes a negative order reverse.) ```ruby class Array def radix_sort(base=10) ary = dup m, max = 1, ary.minmax.map(&:abs).max while m <= max buckets = Array.new(base){[]} ary.each {|n| buckets[(n.abs / m) % base] << n} ary = buckets.flatten m *= base end ary.partition{|n| n<0}.inject{|minus,plus| minus.reverse + plus} end end ``` ## Scala ```Scala object RadixSort extends App { def sort(toBeSort: Array[Int]): Array[Int] = { // Loop for every bit in the integers var arr = toBeSort for (shift <- Integer.SIZE - 1 until -1 by -1) { // The array to put the partially sorted array into val tmp = new Array[Int](arr.length) // The number of 0s var j = 0 // Move the 0s to the new array, and the 1s to the old one for (i <- arr.indices) // If there is a 1 in the bit we are testing, the number will be negative // If this is the last bit, negative numbers are actually lower if ((shift == 0) == (arr(i) << shift >= 0)) arr(i - j) = arr(i) else { tmp(j) = arr(i) j += 1 } // Copy over the 1s from the old array arr.copyToArray(tmp, j, arr.length - j) // And now the tmp array gets switched for another round of sorting arr = tmp } arr } println(sort(Array(170, 45, 75, -90, -802, 24, 2, 66)).mkString(", ")) } ``` ## Sidef {{trans|Ruby}} ```ruby class Array { method radix_sort(base=10) { var arr = self.clone var rounds = ([arr.minmax].map{.abs}.max.ilog(base) + 1) for i in (0..rounds) { var buckets = (2*base -> of {[]}) var base_i = base**i for n in arr { var digit = (n/base_i % base) digit += base if (0 <= n) buckets[digit].append(n) } arr = buckets.flat } return arr } } for arr in [ [1, 3, 8, 9, 0, 0, 8, 7, 1, 6], [170, 45, 75, 90, 2, 24, 802, 66], [170, 45, 75, 90, 2, 24, -802, -66], [100000, -10000, 400, 23, 10000], ] { say arr.radix_sort } ``` {{out}} ```txt [0, 0, 1, 1, 3, 6, 7, 8, 8, 9] [2, 24, 45, 66, 75, 90, 170, 802] [-802, -66, 2, 24, 45, 75, 90, 170] [-10000, 23, 400, 10000, 100000] ``` ## Tailspin ```tailspin templates radixsort@{base:} sink bucketize def value: $; $ / [email protected] -> # <0 ?($value <0..>)> ..|@radixsort.positives: $value; <0> ..|@radixsort.negatives(-1): $value; <> def bucket: $ mod $base -> (($value<0..>)> $ + 1 ! <0> $base ! <> $ !); ..|@radixsort.buckets($bucket): $value; @radixsort.done: 0; end bucketize // Negatives get completed in wrong length-order, we need to collect by length and correct at the end @: { done: 1, digit: 1, positives: [], negatives: [[]], buckets: [1..$base -> []]}; $... -> !bucketize [email protected] -> # <1> [[email protected](-1..1:-1)... ..., [email protected]...] ! <> def previous: [email protected]; ..|@: {done: 1, digit: [email protected] * $base, buckets:[1..$base -> []]}; ..|@.negatives: []; $previous... ... -> !bucketize [email protected] -> # end radixsort [170, 45, 75, 91, 90, 92, 802, 24, 2, 66] -> radixsort@{base:10} -> !OUT::write ' ' -> !OUT::write [-170, -45, -91, -90, -92, -802, -24, -2, -76] -> radixsort@{base:10} -> !OUT::write ' ' -> !OUT::write [170, 45, 75, -91, -90, -92, -802, 24, 2, 66] -> radixsort@{base:10} -> !OUT::write ' ' -> !OUT::write [170, 45, 75, -91, -90, -92, -802, 24, 2, 66] -> radixsort@{base:3} -> !OUT::write ``` {{out}} ```txt [2, 24, 45, 66, 75, 90, 91, 92, 170, 802] [-802, -170, -92, -91, -90, -76, -45, -24, -2] [-802, -92, -91, -90, 2, 24, 45, 66, 75, 170] [-802, -92, -91, -90, 2, 24, 45, 66, 75, 170] ``` ## Tcl {{trans|Python}} ```tcl package require Tcl 8.5 proc splitByRadix {lst base power} { # create a list of empty lists to hold the split by digit set out [lrepeat [expr {$base*2}] {}] foreach item $lst { # pulls the selected digit set digit [expr {($item / $base ** $power) % $base + $base * ($item >= 0)}] # append the number to the list selected by the digit lset out $digit [list {*}[lindex $out $digit] $item] } return $out } # largest abs value element of a list proc tcl::mathfunc::maxabs {lst} { set max [abs [lindex $lst 0]] for {set i 1} {$i < [llength $lst]} {incr i} { set v [abs [lindex $lst $i]] if {$max < $v} {set max $v} } return $max } proc radixSort {lst {base 10}} { # there are as many passes as there are digits in the longest number set passes [expr {int(log(maxabs($lst))/log($base) + 1)}] # For each pass... for {set pass 0} {$pass < $passes} {incr pass} { # Split by radix, then merge back into the list set lst [concat {*}[splitByRadix $lst $base $pass]] } return $lst } ``` Demonstrations: ```tcl puts [radixSort {1 3 8 9 0 0 8 7 1 6}] puts [radixSort {170 45 75 90 2 24 802 66}] puts [radixSort {170 45 75 90 2 24 -802 -66}] ``` Output: ```txt 0 0 1 1 3 6 7 8 8 9 2 24 45 66 75 90 170 802 -802 -66 2 24 45 75 90 170 ``` ## zkl In place int sort, fairly light on garbage creation. ```zkl fcn radixSort(ns){ // ints only, inplace, ns is mutable b:=(0).pump(20,List,List().copy); // 20 [empty] buckets: -10..10 z:=ns.reduce(fcn(a,b){ a.abs().max(b.abs()) },0); // |max or min of input| m:=1; while(z){ ns.apply2('wrap(n){ b[(n/m)%10 +10].append(n) }); // sort on right digit ns.clear(); b.pump(ns.extend); // slam buckets over src b.apply("clear"); // reset buckets m*=10; z/=10; // move sort digit left } ns } ``` ```zkl radixSort(T(170, 45, 75, 90, 802, 2, 24, 66)).println(); radixSort(T(170, 45, 75, -90, -802, 24, 2, 66)).println(); ``` {{out}} ```txt L(2,24,45,66,75,90,170,802) L(-802,-90,2,24,45,66,75,170) ``` {{omit from|GUISS}}