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shiffman/poolselection.js

Created May 1, 2017 20:43
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Pool Selection
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poolselection.js
function pickOne(list) {
var index = -1;
var r = random(1);
while (r > 0) {
index++;
r = r - list[index].prob;
}
return list[index];
}
@akseidel
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I am not sure pickOne(list) does what it is supposed to do when the list is not sorted by list[].prob.

Consider the list 0|.10, 1|.60, 2|.20, 3|.10 where we have four items 0 to 3 having prob. .10, .60, .20 and .10 in that order. The function pickOne(list) will select item 0 when R = .10 or less. The function will select item 1 for any R > .10.

AKS

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