Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

How to randomize sets in math equations ?

  1. Jun 19, 2012 #1
    for example i have this :
    F={1,2,3,4,5}
    so F=1,2,3,4,5
    but how to randomize the set ?
    i want to say F=5,3,4,2,1 or 2,3,1,4,5 or ...

    do i have to say like this? :
    F=(1)/(2)/(3)/(4)/(5)
     
  2. jcsd
  3. Jun 19, 2012 #2

    micromass

    User Avatar
    Staff Emeritus
    Science Advisor
    Education Advisor
    2016 Award

    Some more information could be helpful. Why do you want to "randomize" things?? What is it you're trying to do?
     
  4. Jun 19, 2012 #3
    i want to explain 2 Dice=F
    the F is random of this set : {1,2,3,4,5,6}
    what is the right way to say it ?
    is this right ?
    F={(1.2.3.4.5.6)} ???
     
  5. Jun 19, 2012 #4
    Then all you're saying is that the roll of a die is a random variable that can take on values from 1 to 6.
     
  6. Jun 20, 2012 #5
    so F={(1.2.3.4.5.6)} is the right format to say that ?
    the "." do the random explanation ?
     
  7. Jun 20, 2012 #6

    haruspex

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member
    2016 Award

    A set, like {1, 2, 3, 4, 5, 6}, has no specific order. Neither does it imply anything about relative probabilities. A probability space is more than just the set of possibilities. If you mean them to be equally likely you should say so.
    Btw 'random' does not mean equally likely. It just means not deterministic.
     
  8. Jun 20, 2012 #7
    ok so F={1,2,3,4,5,6} is same as F={(1.2.3.4.5.6)} ?

    update: let me correct myself. so if F={1,2,3} then F can equal (123) or (132) or (213) or ... right ?
     
    Last edited: Jun 20, 2012
  9. Jun 20, 2012 #8

    micromass

    User Avatar
    Staff Emeritus
    Science Advisor
    Education Advisor
    2016 Award

    No, it's not the same. Furthermore, I have not a single idea what you mean with that second notation.

    What are you trying to do??
     
  10. Jun 20, 2012 #9

    haruspex

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member
    2016 Award

    Along with micromass, I have no idea what {(1.2.3.4.5.6)} means. I've never seen such a notation. And I don't know what you mean by F = (123) etc. F is a set, pure and simple, specifically, the set of possible outcomes from one trial.
     
  11. Jun 20, 2012 #10
    No. You don't seem to understand the notion of a set.
    F = {1, 2, 3} means that F, as a set, contains the elements 1, 2 and 3. There is no order implied. None. Sets have no notion of order, and the idea of "randomizing a set" makes no sense at all, nor does the notation "F = {(1.2.3)}".
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook