FoxPro Unique Random Number - visual-foxpro

Question

Could some one help, Looking for Unique random generated number.
Currently have 4 pubs, If data have more than 4 pubs, need randomly select the pubs and place the value to Pub1 Pub2 Pub3 and Pub4 fields. Can't find solution by using FoxPro.
SELE A
USE TEST
REPL PUB1 WITH "" ALL
REPL PUB2 WITH "" ALL
REPL PUB3 WITH "" ALL
REPL PUB4 WITH "" ALL
REPL RANDOM1 WITH "" ALL
REPL RANDOM2 WITH "" ALL
REPL RANDOM3 WITH "" ALL
REPL RANDOM4 WITH "" ALL
REPL RANDOMLOG WITH "" ALL
SELE B
USE WHATPUB
SELE A
GO TOP
DO WHILE !EOF()
cBRANCH=BRANCH
SELE B
SET FILTER TO BRANCH=cBRANCH
COUN TO nBRANCHQTY
IF nBRANCHQTY<=4
FOR loop=1 TO nBRANCHQTY
SELE B
LOCA FOR loop=FT_URN
IF FOUND()
cPUBID=PUBID
SELE A
cFLD1="PUB"+LTRIM(STR(loop))
REPL (cFLD1) WITH cPUBID
ENDIF
NEXT loop
ELSE
SELE A
FOR loop=1 TO 4
SELE A
DO WHILE nRANDOMPUB>nBRANCHQTY
nRANDOMPUB=INT(RAND()*10)+1
ENDDO
SELE B
LOCATE FOR nRANDOMPUB=FT_URN
IF FOUND()
cPUBID=PUBID
SELE A
cFLD1="PUB"+LTRIM(STR(loop))
cFLD2="RANDOM"+LTRIM(STR(loop))
REPL (cFLD1) WITH cPUBID
REPL (cFLD2) WITH LTRIM(STR(nRANDOMPUB))
ENDIF
nRANDOMPUB=9999999
NEXT loop
ENDIF
SELE A
SKIP
ENDDO
GO TOP
BROW FIELDS BRANCH,RANDOMLOG,RANDOM1,PUB1,RANDOM2,PUB2,RANDOM3,PUB3,RANDOM4,PUB4
If something is not understandable, just let me know.

Answer 1

You are using int(rand() * 10) + 1. Be it VFP or any other language your intent is to select a random number between 1 and 10. There is nothing in your code that says it should be unique Pub1, Pub2, ... It is normal that repeated calls to rand may return same value when you are choosing 4 values out of max 10. Instead you could do something like this (untested off the top of my head):
Create Cursor crsRand (pubVal i)
Local ix
For ix = 1 To 10
Insert Into crsRand Values (m.ix)
Endfor
Rand(-1)
Select 0
Use TEST
Replace PUB1 With "", ;
PUB2 With "", ;
PUB3 With "", ;
PUB4 With "", ;
RANDOM1 With "", ;
RANDOM2 With "", ;
RANDOM3 With "", ;
RANDOM4 With "", ;
RANDOMLOG With "" All
Use WHATPUB In 0
Local cBRANCH, nBranch, nBRANCHQTY, Loop, cPubId, cFld1
Local Array laRandPub[1]
Select TEST
Scan
cBRANCH=BRANCH
Select WHATPUB
Count For BRANCH=m.cBRANCH To nBRANCHQTY
If m.nBRANCHQTY<=4
Select WHATPUB
For Loop=1 To m.nBRANCHQTY
Locate For FT_URN=m.loop
If Found()
cPubId=PUBID
Select TEST
cFld1="PUB"+Ltrim(Str(m.loop))
Replace (m.cFld1) With m.cPubId
Endif
Endfor
Else
Select pubVal From ;
(Select Top 4 pubVal, Rand() From crsRand Where pubVal <= m.nBRANCHQTY Order By 2) tmp ;
into Array laRandPub
For Loop=1 To 4
Select WHATPUB
Locate For FT_URN=laRandPub[m.loop]
If Found()
select Test
cPubId=PUBID
cFld1="PUB"+Ltrim(Str(m.loop))
cFLD2="RANDOM"+Ltrim(Str(m.loop))
Repl (m.cFld1) With m.cPubId, (m.cFLD2) With Ltrim(Str(laRandPub[m.loop]))
Endif
Endfor
Endif
Endscan
Locate
Brow Fields BRANCH,RANDOMLOG,RANDOM1, ;
PUB1,RANDOM2,PUB2,RANDOM3,PUB3,RANDOM4,PUB4
Note that Select A, Select B style coding is dangerous. Use aliases instead.