Albert, your solution looks pretty good. However, when I "played" with it, I found something interesting. When I am having problems with a statement or trying to learn how something works, I often break apart the complex portions into their "atomic units". While doing this with your approach I observed something that, to me, is very subtle and very discrete about SELECT-processing versus FUNCTION-processing.
>From the SELECT below, notice that the values for #TIME are constant; I assume that by whatever means the parsing and processing work within RBase (or any other DBMS, probably) the value for this is fixed at some point therein. However, you can see that both (TEXTRACT(.#NOW)) as well as your input to RANDOM, (FLOAT(format(.#time,'hhmmss.ss'))) process once for each row in the result-set. ALSO, for further observation, when I replicated these sets of values (%NUM and %Result 2 & 3), it seems that those function calls are likewise executed each time they are called within a row of the result. In this case, 3 times, which is as one would expect, such as when using a stored procedure. This successive execution by call within each row also demonstrates that RANDOM() appears to function as advertised. Although I haven't saved/assessed the data to prove this, the limited matrix generated below shows no duplicate values, based on an "eyeball" of the result-set. I'm sure it's all correct for how a dbms engine (and other functionality associated with the implementation) but I found it curious and thought that maybe others might learn from this little demonstration of nuance, as I just did. R>sho time TIME format HH:MM:SS.SSS TIME sequence HHMMSS R>select .#TIME AS #TIME, (TEXTRACT(.#NOW)) AS TIME_fm_#NOW, (FLOAT(format(.#time,'hhmmss.sss'))) AS AlbertsNUM1, (random(INT(1000 * (FLOAT(format(.#time,'hhmmss.sss')))))) AS RandomNUM1, (FLOAT(format(.#time,'hhmmss.sss'))) AS AlbertsNUM2, (random(INT(1000 * (FLOAT(format(.#time,'hhmmss.sss')))))) AS RandomNUM2, (FLOAT(format(.#time,'hhmmss.sss'))) AS AlbertsNUM3, (random(INT(1000 * (FLOAT(format(.#time,'hhmmss.sss')))))) AS RandomNUM3 from sys_tables #TIME TIME_fm_#NOW AlbertsNUM1 RandomNUM1 AlbertsNUM2 RandomNUM2 AlbertsNUM3 RandomNUM3 --------------- ------------ --------------- ---------- --------------- ---------- --------------- ---------- 13:49:30.360 13:49:30.361 134930.361 72221179 134930.361 111570377 134930.361 65546310 13:49:30.360 13:49:30.440 134930.44 50969512 134930.44 112665764 134930.44 40864553 13:49:30.360 13:49:30.462 134930.462 96252427 134930.462 17788683 134930.462 55457869 13:49:30.360 13:49:30.479 134930.479 15672161 134930.479 33794386 134930.479 132414532 13:49:30.360 13:49:30.497 134930.497 7716667 134930.497 115206464 134930.497 75795460 ... 13:50:19.637 13:50:23.832 135023.832 94740843 135023.833 23392648 135023.833 40480778 13:50:19.637 13:50:23.851 135023.851 102491706 135023.851 50382587 135023.851 12332958 13:50:19.637 13:50:23.870 135023.87 48042092 135023.87 21727931 135023.87 106591719 Just sittin' here watchin' the world go by ... Steve in Memphis -----Original Message----- From: [email protected] [mailto:[EMAIL PROTECTED] On Behalf Of Albert Berry Sent: Tuesday, April 08, 2008 12:11 PM To: RBASE-L Mailing List Subject: [RBASE-L] - Re: [SPAM] [RBASE-L] - Random numbers R:Base uses a pseudo random number generator. You can use the system time variable to the 1/1,000 second to generate pseudo random numbers that are for all intents and purposes random. Here is an example select (random(INT(1000 * (FLOAT(format(.#time,"hhmmss.sss")))))) from sys_tables where count = 1 Marc wrote: > I just tested this 3 times and get the same numbers each time. > I am setting the Random number to 15 and created 10 > The numbers I get are > 0 0 5 0 5 3 8 2 10 14 each of the 3 times I tested this. > > I hope I am missing something, I sent an update out several months > back that needs truley random numbers. > > Marc >
