Math.Random is not random enough

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-1

I noticed that if I use the Math.random with values from 0 to 10, it is very possible that the result will be repeated or generate an approximate value of the previous.

For example, I executed:

function random() {
    return Math.floor(Math.random() * 10);
}

and left:

Math.random não tão aleatório

If it exists, how do I generate even more random values?

javascript
  • 3

    Based on what do you claim that Math.Random() is not random enough? Strong claims like this call for strong evidence. What tests have you done, besides printing half a dozen samples? Which Javascript implementation are you testing and claim to be bad?

  • good, for what I’m trying to do, really it’s not, I put the function random upstairs for you to test. I’m not saying it’s bad, I just want to prevent repeated numbers from being displayed less frequently, because the lower the maximum number, the more likely it is to be repeated frequently

  • 2

    The way you did, it will only generate numbers between 0 and 9, so of course after a few runs you will get repeat, and the more times you run, the more chances you will repeat. What exactly do you want to do?

  • wanted to have a larger variation if it ran again

1 answer

1


As described: "...it is very possible that the result will be repeated or generate an approximate value of the previous one." There are explanations of why there is no way a computer can generate truly random numbers. And how the crease of numbers that exemplified is small, is expected a variation between them to be less, given that the chance of falling the same number after the previous one is still the same within 0 to 10.

You can increase their limit (by replacing the maximum value by 100) and make an implementation as specified in mozilla documentation: Math.floor(Math.random() * Math.floor(100)); to obtain a greater variation. In the mentioned documentation is also explained how to generate random numbers with greater security.

I recommend researching more about randomly generated numbers by computers.

I hope I’ve helped in some way.

  • I’ll take a look

  • So there’s nothing I can do... Anyway, thank you for clarifying. I even tried to use several randoms and make the average, but it seems that reduced the randomness even more.

  • 1

    I even agree with saying that "there are explanations of why there is no way for a computer to generate truly random numbers," but I don’t believe that this is related to the author’s problem (there is even a demonstrated problem, in fact). Edit: this is not a problem in the answer, I only left as an observation in the sense that the author of the question does not improperly associate the perception with the explanation of the link.

  • 1

    Yeah, @Bacco, you’re right. I inserted it only because I considered it pertinent to the subject matter addressed in the question, along with a demonstration of how to "decrease randomness" (and actually, there is no problem in fact reported in the question).

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