langs a-z

Task/Forward-difference/NetRexx/forward-difference.netrexx

@@ -0,0 +1,34 @@
+/* NetRexx*************************************************************
+* Forward differences
+* 18.08.2012 Walter Pachl derived from Rexx
+**********************************************************************/
+  Loop n=-1 To 11
+    differences('90 47 58 29 22 32 55 5 55 73',n)
+    End
+
+  method differences(a,n) public static
+  --arr=Rexx[11]                       -- array must be declared (zero based)
+    arr=''                             -- alternative: indexed string
+    m=a.words
+    Select
+      When n<0 Then Say 'n is negative:' n '<' 0
+      When n>m Then Say 'n is too large:' n '>' m
+      Otherwise Do
+        Loop i=1 To m
+          arr[i]=a.word(i)
+          End
+        Loop i = 1 to n
+          t = arr[i]
+          Loop j = i+1 to m
+            u = arr[j]
+            arr[j] = arr[j]-t
+            t = u
+            end
+          end
+        ol=''
+        Loop i=n+1 to m
+          ol=ol arr[i]
+          End
+        Say n ol
+        End
+      End

Task/Forward-difference/Nial/forward-difference-1.nial

@@ -0,0 +1 @@
+fd is - [rest, front]

Task/Forward-difference/Nial/forward-difference-2.nial

@@ -0,0 +1,3 @@
+b := 90 47 58 29 22 32 55 5 55 73
+4 fold fd b
+= 156 -67 1 -82 259 -305

Task/Forward-difference/OCaml/forward-difference.ocaml

@@ -0,0 +1,11 @@
+let rec forward_difference = function
+    a :: (b :: _ as xs) ->
+      b - a :: forward_difference xs
+  | _ ->
+      []
+
+let rec nth_forward_difference n xs =
+  if n = 0 then
+    xs
+  else
+    nth_forward_difference (pred n) (forward_difference xs)

Task/Forward-difference/Objeck/forward-difference.objeck

@@ -0,0 +1,36 @@
+bundle Default {
+  class Test {
+    function : Main(args : String[]) ~ Nil {
+      a := [90.0, 47.0, 58.0, 29.0, 22.0, 32.0, 55.0, 5.0, 55.0, 73.0];
+      Print(Diff(a, 1));
+      Print(Diff(a, 2));
+      Print(Diff(a, 9));
+    }
+
+    function : Print(a : Float[]) ~ Nil {
+      if(a <> Nil) {
+        '['->Print();
+        each(i : a) {
+          a[i]->Print(); ','->Print();
+        };
+        ']'->PrintLine();
+      };
+    }
+
+    function : Diff(a : Float[], n : Int) ~ Float[] {
+      if (n < 0) {
+        return Nil;
+       };
+
+      for(i := 0; i < n & a->Size() > 0; i += 1;) {
+        b := Float->New[a->Size() - 1];
+        for(j := 0; j < b->Size(); j += 1;){
+          b[j] := a[j+1] - a[j];
+        };
+        a := b;
+      };
+
+      return a;
+    }
+  }
+}

Task/Forward-difference/PARI-GP/forward-difference.pari

@@ -0,0 +1 @@
+fd(v)=vector(#v-1,i,v[i+1]-v[i]);

Task/Forward-difference/PL-I/forward-difference.pli

@@ -0,0 +1,21 @@
+/* Forward differences. */ /* 23 April 2010 */
+differences: procedure options (main);
+   declare a(10) fixed(10) static initial
+      (7, 3, 9, 250, 300, 4, 68, 72, 154, 601);
+   declare (i, j, m, n, t, u) fixed binary;
+
+   m = hbound(a,1);
+   get (n); if n > m then signal error;
+   put skip edit (a) (F(7));
+   do i = 1 to n;
+      t = a(i);
+      do j = i+1 to m;
+         u = a(j);
+         a(j) = a(j) - t;
+         t = u;
+      end;
+      put skip edit (a) (F(7));
+   end;
+   put skip edit ((a(i) do i = n+1 to m)) (F(9));
+
+end differences;

Task/Forward-difference/Pascal/forward-difference.pascal

@@ -0,0 +1,26 @@
+Program ForwardDifferenceDemo(output);
+
+procedure fowardDifference(list: array of integer);
+  var
+    b: array of integer;
+    i, newlength: integer;
+  begin
+    newlength := length(list) - 1;
+    if newlength > 0 then
+    begin
+      setlength(b, newlength);
+      for i := low(b) to high(b) do
+      begin
+        b[i] := list[i+1] - list[i];
+        write (b[i]:6);
+      end;
+      writeln;
+      fowardDifference(b);
+    end;
+  end;
+
+var
+  a: array [1..10] of integer = (90, 47, 58, 29, 22, 32, 55, 5, 55, 73);
+begin
+  fowardDifference(a);
+end.

Task/Forward-difference/Perl-6/forward-difference.pl6

@@ -0,0 +1,2 @@
+sub dif(@array [$, *@tail]) { @tail Z- @array }
+sub difn($array, $n) { ($array, &dif ... *)[$n] }

Task/Forward-difference/Pop11/forward-difference.pop11

@@ -0,0 +1,20 @@
+define forward_difference(l);
+    lvars res = [], prev, el;
+    if l = [] then
+        return([]);
+    endif;
+    front(l) -> prev;
+    for el in back(l) do
+        cons(el - prev, res) -> res;
+        el -> prev;
+    endfor;
+    rev(res);
+enddefine;
+
+define nth_difference(l, n);
+    lvars res = l, i;
+    for i from 1 to n do
+        forward_difference(res) -> res;
+    endfor;
+    res;
+enddefine;

Task/Forward-difference/PowerShell/forward-difference.psh

@@ -0,0 +1,22 @@
+function Forward-Difference( [UInt64] $n, [Array] $f )
+{
+	$flen = $f.length
+	if( $flen -gt [Math]::Max( 1, $n ) )
+	{
+		0..( $flen - $n - 1 ) | ForEach-Object {
+			$l=0;
+			for( $k = 0; $k -le $n; $k++ )
+			{
+				$j = 1
+				for( $i = 1; $i -le $k; $i++ )
+				{
+					$j *= ( ( $n - $k + $i ) / $i )
+				}
+				$l += $j * ( 1 - 2 * ( ( $n - $k ) % 2 ) ) * $f[ $_ + $k ]
+			}
+			$l
+		}
+	}
+}
+
+Forward-Difference 2 1,2,4,5

Task/Forward-difference/PureBasic/forward-difference.purebasic

@@ -0,0 +1,53 @@
+Procedure forward_difference(List a())
+  If ListSize(a()) <= 1
+    ClearList(a()): ProcedureReturn
+  EndIf
+  Protected NewList b()
+  CopyList(a(), b())
+  LastElement(a()): DeleteElement(a())
+  SelectElement(b(), 1)
+  ForEach a()
+    a() - b(): NextElement(b())
+  Next
+EndProcedure
+
+Procedure nth_difference(List a(), List b(), n)
+  Protected i
+  CopyList(a(), b())
+  For i = 1 To n
+    forward_difference(b())
+  Next
+EndProcedure
+
+Procedure.s display(List a())
+  Protected output.s
+  ForEach a()
+    output + Str(a()) + ","
+  Next
+  ProcedureReturn RTrim(output,",")
+EndProcedure
+
+DataSection
+  ;list data
+  Data.i 10 ;element count
+  Data.i 90, 47, 58, 29, 22, 32, 55, 5, 55, 73
+EndDataSection
+
+;create and fill list
+Define i
+NewList a()
+Read.i i
+While i > 0
+  AddElement(a()): Read.i a(): i - 1
+Wend
+
+If OpenConsole()
+  NewList b()
+  For i = 1 To 10
+    nth_difference(a(), b(), i)
+    PrintN(Str(i) + "   [" + display(b()) + "]")
+  Next
+
+  Print(#CRLF$ + #CRLF$ + "Press ENTER to exit"): Input()
+  CloseConsole()
+EndIf

Task/Forward-difference/SQL/forward-difference.sql

@@ -0,0 +1,37 @@
+create table list (n integer, v real);
+insert into list values (0, 90);
+insert into list values (1, 47);
+insert into list values (2, 58);
+insert into list values (3, 29);
+insert into list values (4, 22);
+insert into list values (5, 32);
+insert into list values (6, 55);
+insert into list values (7, 5);
+insert into list values (8, 55);
+insert into list values (9, 73);
+
+create view diff1 as select list.n, (select next.v from list as next where next.n = list.n + 1) - list.v as v from list;
+create view diff2 as select list.n, (select next.v from diff1 as next where next.n = list.n + 1) - list.v as v from diff1 as list;
+
+select * from diff1;
+    0|-43.0
+    1|11.0
+    2|-29.0
+    3|-7.0
+    4|10.0
+    5|23.0
+    6|-50.0
+    7|50.0
+    8|18.0
+    9|
+select * from diff2;
+    0|54.0
+    1|-40.0
+    2|22.0
+    3|17.0
+    4|13.0
+    5|-73.0
+    6|100.0
+    7|-32.0
+    8|
+    9|

Task/Forward-difference/Seed7/forward-difference.seed7

@@ -0,0 +1,33 @@
+$ include "seed7_05.s7i";
+
+const func array integer: forwardDifference (in array integer: data) is func
+  result
+    var array integer: diffResult is 0 times 0;
+  local
+    var integer: index is 0;
+  begin
+    for index range 1 to pred(length(data)) do
+      diffResult &:= -data[index] + data[succ(index)];
+    end for;
+  end func;
+
+const proc: main is func
+  local
+    var array integer: data is [] (90, 47, 58, 29, 22, 32, 55, 5, 55, 73);
+    var integer: level is 0;
+    var integer: number is 0;
+    var boolean: firstElement is TRUE;
+  begin
+    for level range 0 to length(data) do
+      firstElement := TRUE;
+      for number range data do
+        if not firstElement then
+          write(", ");
+        end if;
+        firstElement := FALSE;
+        write(number);
+      end for;
+      writeln;
+      data := forwardDifference(data);
+    end for;
+  end func;

Task/Forward-difference/Slate/forward-difference-1.slate

@@ -0,0 +1,17 @@
+s@(Sequence traits) forwardDifference
+[
+  s allButFirst with: s allButLast collect: #- `er
+].
+
+s@(Sequence traits) forwardDifference
+"Without creating two intermediate throwaway Sequences."
+[
+  result ::= s allButFirst.
+  result doWithIndex: [| :nextValue :index | result at: index infect: [| :oldValue | oldValue - (s at: index)].
+  result
+].
+
+s@(Sequence traits) forwardDifference: n
+[
+  (0 below: n) inject: s into: [| :seq :_ | seq forwardDifference]
+].

Task/Forward-difference/Slate/forward-difference-2.slate

@@ -0,0 +1,2 @@
+#data := ##(90 47 58 29 22 32 55 5 55 73).
+data keysDo: [| :index | inform: (data forwardDifference: index) printString].

Task/Forward-difference/Standard-ML/forward-difference.ml

@@ -0,0 +1,7 @@
+fun forward_difference xs = ListPair.map op- (tl xs, xs)
+
+fun nth_forward_difference n xs =
+  if n = 0 then
+    xs
+  else
+    nth_forward_difference (n-1) (forward_difference xs)

Task/Forward-difference/Ursala/forward-difference-1.ursala

@@ -0,0 +1,5 @@
+#import std
+#import nat
+#import flo
+
+nth_diff "n" = rep"n" minus*typ

Task/Forward-difference/Ursala/forward-difference-2.ursala

@@ -0,0 +1,9 @@
+test_data = <90.,47.,58.,29.,22.,32.,55.,5.,55.,73.>
+
+#show+
+
+examples =
+
+printf/*=*' %0.0f' <
+   nth_diff6 test_data,
+   nth_diff7 test_data>

Task/Forward-difference/Visual-Basic-.NET/forward-difference.visual

@@ -0,0 +1,22 @@
+Module ForwardDifference
+
+    Sub Main()
+        Dim lNum As New List(Of Integer)(New Integer() {90, 47, 58, 29, 22, 32, 55, 5, 55, 73})
+        For i As UInteger = 0 To 9
+            Console.WriteLine(String.Join(" ", (From n In Difference(i, lNum) Select String.Format("{0,5}", n)).ToArray()))
+        Next
+        Console.ReadKey()
+    End Sub
+
+    Private Function Difference(ByVal Level As UInteger, ByVal Numbers As List(Of Integer)) As List(Of Integer)
+        If Level >= Numbers.Count Then Throw New ArgumentOutOfRangeException("Level", "Level must be less than number of items in Numbers")
+
+        For i As Integer = 1 To Level
+            Numbers = (From n In Enumerable.Range(0, Numbers.Count - 1) _
+                       Select Numbers(n + 1) - Numbers(n)).ToList()
+        Next
+
+        Return Numbers
+    End Function
+
+End Module