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Weighted random value in underscore or lodash
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| ## First you can generate a weighted array | |
| weighted 1: true, 2: false # [true, false, false] | |
| weighted 1: true, 3: false # [true, false, false, false] | |
| ## Then random picks one randomly | |
| ## The following will return true or false with a 1:3 ratio | |
| random weighted 1: true, 3: false | |
| # here's the magic, you need underscore or lodash | |
| weighted = (weightMap) -> | |
| _ weightMap | |
| .map (val, weight) -> _.times weight, -> val | |
| .flatten() | |
| .value() | |
| random = (arr) -> _.shuffle(arr)[0] |
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You can replace
_.shuffle(arr)[0]by_.pick(arr)I believe!