Vista - Randomize a one dimentional array

Does anyone know how I can randomize a one dimentional array with VBscript. I
would like it to pull back the values with no duplicates.

e.g.

mysting = "this" & vbcrlf & "is" & vbcrlf & "a" & vbcrlf & "test"
myarr = split(mystring,vbcrlf)

On Thu, 02 Oct 2008 16:30:01 GMT, =?Utf-8?B?Qm9iIFNtaXRo?= wrote:
Copy the items in random order from the source array to a second array. As
each item is copied from the source array, replace it with the last item in
the array, then decrease the size of the array by 1. When you hit 0, you're
done.

There are better ways to do this, of course, but this is a very simple
method that I've used in a few places. This code should do what you want:

RANDOMIZE TIMER
source = ARRAY("this", "is", "a", "test")
ubSrc = UBOUND(source)

REDIM target(ubSrc)

FOR L0 = ubSrc TO 1 STEP -1 ' the actual work is in this loop
tmp = INT(RND * (L1 + 1))
target(L1) = source(tmp)
source(tmp) = source(L1)
REDIM PRESERVE source(L1 - 1)
NEXT

target(0) = source(0)

outP = target(0)
FOR L0 = 1 TO ubSrc
outP = outP & VBCRLF & target(L1)
NEXT

MSGBOX outP

This works for many similar situations, i.e. card shuffling.

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What is the difference between Nintendo64 and Commodore64?

Bob Smith schrieb:See topic "How to Randomize characters in a string" (2008-08-19)
in this group

Auric__ schrieb:Because L1 is not initialized/empty/0, source is clobbered
here immediately: (L1 - 1) == -1.

Thanks Auric__ but the code does not seem to work. subscript out of range:
'tmp'. I'm not sure why but it looks like value L1 is not defined? What
should L1 be?



"Auric__" wrote:

On Thu, 02 Oct 2008 17:57:20 GMT, ekkehard.horner wrote:
Whoops. That's a think-o. Change all instances of L1 to L0 (or L0 to L1,
doesn't matter). Should be:

FOR L0 = ubSrc TO 1 STEP -1
tmp = INT(RND * (L0 + 1))
target(L0) = source(tmp)
source(tmp) = source(L0)
REDIM PRESERVE source(L0 - 1)
NEXT

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There might be room at the top but there is seldom enough time.

On Thu, 02 Oct 2008 18:14:12 GMT, =?Utf-8?B?Qm9iIFNtaXRo?= wrote:
As ekkehard.horner pointed out, there's a screw-up in what I posted.
Corrected version, works for me:

RANDOMIZE TIMER
source = ARRAY("this", "is", "a", "test")
ubSrc = UBOUND(source)

REDIM target(ubSrc)

FOR L1 = ubSrc TO 1 STEP -1
tmp = INT(RND * (L1 + 1))
target(L1) = source(tmp)
source(tmp) = source(L1)
REDIM PRESERVE source(L1 - 1)
NEXT

target(0) = source(0)

outP = target(0)
FOR L1 = 1 TO ubSrc
outP = outP & VBCRLF & target(L1)
NEXT

MSGBOX outP

(That's what I get for posting before my daily caffiene IV. [sigh])

--
Welcome and keep out.

Auric__ schrieb:[...]
Please test your code before posting - now you generate an
array with 4 identical string items.

ekkehard.horner schrieb:Sorry, my fault: you generate a correct array, but the display
code repeats the L1==0==uninitialized value

On Thu, 02 Oct 2008 19:00:53 GMT, ekkehard.horner wrote:
Please see my second response to the OP. (Me - caffiene = bad.)

I should've just posted my actual code (a card shuffling test) that does
this:

-----begin shufler4.vbs-----
Option Explicit

Const ForReading = 1
Const ForWriting = 2

Dim unShuffled
Dim Shuffled(51)
Dim L0, card, fO
Dim FSO

unShuffled = Array("AS", "2S", "3S", "4S", "5S", "6S", "7S", "8S", "9S", _
"10S", "JS", "QS", "KS", "AH", "2H", "3H", "4H", "5H", "6H", "7H", _
"8H", "9H", "10H", "JH", "QH", "KH", "AC", "2C", "3C", "4C", "5C", _
"6C", "7C", "8C", "9C", "10C", "JC", "QC", "KC", "AD", "2D", "3D", _
"4D", "5D", "6D", "7D", "8D", "9D", "10D", "JD", "QD", "KD")

Randomize Timer

For L0 = 51 To 0 Step -1
card = Int(Rnd * (L0 + 1))
Shuffled(L0) = unShuffled(card)
If card <> L0 Then unShuffled(card) = unShuffled(L0)
Next

Set FSO = WScript.CreateObject("Scripting.FileSystemObject")

Set fO = FSO.OpenTextFile("shuf4.txt", ForWriting, True)
For L0 = 0 To 51
fO.WriteLine Shuffled(L0)
Next
fO.Close
-----end shufler4.vbs-----

(Note that I don't resize the array in this version.)

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kill -9 needs no justification!
-- BOfH