Random function

[Pyrokid]

This is somthing that has been bothering me for awhile. In my math class my teacher was talking about how if you reset 2 of the same calculators and used the randint() function you would get the same answer on both calcs. He said somthing about the random number algo is not exactly random. And i was wondering how exactly does a computer select a number at random?

[Dio]

Doesn’t a computer pick it's "seed" number from timer?
and since it is almost impossible to start a program at the same time the numbers appear random?

or you could hook a geiger counter up to your PC and get a piece of radio active material. that would work.

http://computer.howstuffworks.com/question697.htm

[Zap]

It only takes the seed from the timer if you tell it to. If you don't seed it with the timer (or some other constantly changing number) you will always get the same series of numbers, due to the fact that there is no such thing as true randomity (if thats a word) only unpredictability.

[Pyrokid]

Ok but what about a calulator that doesnt come equiped with a timer the only other seed that i could think of is user input but that isnt reliable.

[Deleter]

Put a piece of radioactive material inside your calcuator with a geiger counter?
Or maybe if its possible, get the voltage or something left in the batteries, since the batteries are the only non static element in your calcuator.

[urger]

Our lab uses radio static to determine random numbers

[Pyrokid]

Or maybe if its possible, get the voltage or something left in the batteries, since the batteries are the only non static element in your calcuator.

No thats not it its somthing to do with how you use the calculator because like i said earlyer if you reset 2 of the same kind of calculators (ie ti83,ti83+) and use the randint() you will get the same answer

[Dio]

oh my, i just made an ass out of myself...(not the first time )

[rpgfan3233]

No thats not it its somthing to do with how you use the calculator because like i said earlyer if you reset 2 of the same kind of calculators (ie ti83,ti83+) and use the randint() you will get the same answer

I figured that's what you meant. ;-)

I think it uses its internal timer (how else would the TI-84+ keep track of the time?) to generate a random number and then uses that number with a RANDOMIZE statement (in terms of QB) rather than using RANDOMIZE TIMER to generate the numbers.

[Deleter]

none of the TI's that I know of keep track of the time....and I know the TI 83 doesn't and that the TI 86 doesn't, maybe the 84 does, thought that wouldn't make too much sense...