Re^2: Random generator fail

Ok I have better understanding now, Bill your solutions works great!

@MidLifeXis What is rational for rand to ignore $_. Appearently you pointing out that, solves my problem by using

perl -wle "use 5.10.0;  foreach (1..100) { say rand($_);};"

1.94992065429688
56.7288208007813
52.1597290039063
18.6995849609375
6.6961669921875
68.6776733398438
65.6177978515625
62.72314453125
52.1324157714844
...
[download]

But I think using additional line { say rand($_); is completely un-neccessary. Thank you.

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Re^3: Random generator fail by MidLifeXis (Monsignor) on Dec 06, 2012 at 18:44 UTC
Let's step through this: `foreach (1..100) { say rand($_); }` [download] When `$_` is equal to ... ... 1, rand($_) cannot be larger than 1. ... 2, rand($_) cannot be larger than 2. ... 3, rand($_) cannot be larger than 3. ... 4, rand($_) cannot be larger than 4. ... 5, rand($_) cannot be larger than 5. ... 6, rand($_) cannot be larger than 6. Look at one of my earlier posts on this thread. The documentation for rand states that `0 <= rand($x) < $x` if $x > 0. To accomplish what you are trying to do would require that you do this: `say 1 + rand(99 - 1) for (1..100)` [download] In my previous node, MAX = 99 and MIN = 1. The 1..100 is the number of iterations you wish to use. If you use `rand($_)`, your results will be biased toward the lower end of the counter range. --MidLifeXis	[reply] [d/l] [select]
Re^4: Random generator fail by Anonymous Monk on Dec 06, 2012 at 20:12 UTC
I agree with bias at lower end. Great, that is pretty much what I was looking for. Thank you	[reply]
Re^3: Random generator fail by BillKSmith (Monsignor) on Dec 06, 2012 at 23:00 UTC
My `rand 98` generates random numbers in the range (0<= number < 98). Adding one to every random number changes the range to (1<=number<99). Using `rand $_` would generate a very different sequence of numbers. In fact, the sample output that you show cannot be the first few numbers as your dots suggest. It is possible that they are the last few numbers. Bill	[reply] [d/l] [select]
Re^3: Random generator fail by Anonymous Monk on Dec 06, 2012 at 14:07 UTC
forgot to add this: `perl -wle "use 5.10.0; say int foreach (1..100) ;"` [download] Works as rand() should have.	[reply] [d/l]
Re^4: Random generator fail by MidLifeXis (Monsignor) on Dec 06, 2012 at 17:23 UTC
Works as rand() should have. Either your assumptions are wrong, or the documentation for rand does not match the implementation. Which do you think it is? --MidLifeXis	[reply]
Re^4: Random generator fail by Anonymous Monk on Dec 06, 2012 at 14:22 UTC
This one is better `perl -wle "use 5.10.0; say abs foreach (-5..5) ;" 5 4 3 2 1 0 1 2 3 4 5` [download]	[reply] [d/l]