Scratch

Jonathanpb · 2009-11-22 05:11:24

Just curious. smile

what-the · 2009-11-22 06:04:30

This would be interesting as visual basic (well microsofts visual basic) are the same random numbers every time on every computer that runs it.

UGWG · 2009-11-22 07:19:09

IF they did it JavaScript they use a simple script (of course they used an easier one in Java)
var x=Math.floor(Math.random()*99) and that would be 1 to 100.

greenflash · 2009-11-22 11:41:02

I believe it uses some sort of algorithm, but I'm not sure what that algorithm is...

fg123 · 2009-11-22 12:22:29

Maybe it uses the id number of the program and does some random calculations to make it equal * , then it has 1 second to run through the numbers you listed and stop at the * number??

Chrischb · 2009-11-22 21:29:51

One of the hardest things for people to program is a random number picker. It's usually done by creating a list, dividing, rounding, etc.. Another method is messing around with the time... what does Scratch use?

At least we should be glad that we have the random block. smile

Locomule · 2009-11-22 23:27:24

It uses a variable gate dynamic oscillator that syncs the cpu load at a given moment with the speed fluctuation of a virtual cd-rom burning a bit-reduced copy of Judas Priest's Rocka Rolla. Then it multiplies (or divides) the result (and does abs if necessary) to derive the sweep range.

fg123 · 2009-11-22 23:29:22

Really?

Jonathanpb · 2009-11-22 23:42:23

Locomule wrote:
It uses a variable gate dynamic oscillator that syncs the cpu load at a given moment with the speed fluctuation of a virtual cd-rom burning a bit-reduced copy of Judas Priest's Rocka Rolla. Then it multiplies (or divides) the result (and does abs if necessary) to derive the sweep range.

Thanks! smile

WeirdF · 2009-11-23 15:30:14

Well whatever it is, it is not technically random. All of these methods people have suggested aren't random, they are just unpredictable.

BoltBait · 2009-11-23 17:24:05

Without looking into the Scratch source code, but knowing a bit about computer generated random numbers (pseudo-random numbers), I would bet that Scratch uses a Linear Congruential random number generator.

More info here: http://en.wikipedia.org/wiki/Linear_congruential_generator

It is extremely fast, and if the coefficients c, m, and a are chosen properly it has a very large period and a very good distribution.

Jwosty · 2010-01-27 21:27:54

fg123 wrote:
Maybe it uses the id number of the program and does some random calculations to make it equal * , then it has 1 second to run through the numbers you listed and stop at the * number??

That's not possible, because to make a random calculation it would have to use itself to generate the numbers for the calculation, but it couldn't. Do you see what I mean?

Scratch

archived forums

#1 2009-11-22 05:11:24

What does Scratch use to pick random numbers?

#2 2009-11-22 06:04:30

Re: What does Scratch use to pick random numbers?

#3 2009-11-22 07:19:09

Re: What does Scratch use to pick random numbers?

#4 2009-11-22 11:41:02

Re: What does Scratch use to pick random numbers?

#5 2009-11-22 12:22:29

Re: What does Scratch use to pick random numbers?

#6 2009-11-22 21:29:51

Re: What does Scratch use to pick random numbers?

#7 2009-11-22 23:27:24

Re: What does Scratch use to pick random numbers?

#8 2009-11-22 23:29:22

Re: What does Scratch use to pick random numbers?

#9 2009-11-22 23:42:23

Re: What does Scratch use to pick random numbers?

Locomule wrote:

#10 2009-11-23 15:30:14

Re: What does Scratch use to pick random numbers?

#11 2009-11-23 17:24:05

Re: What does Scratch use to pick random numbers?

#12 2010-01-27 21:27:54

Re: What does Scratch use to pick random numbers?

fg123 wrote:

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