22 lines
487 B
JavaScript
22 lines
487 B
JavaScript
(function (xs) {
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return xs.reduce(function (a, x, i) {
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var n = i + 1,
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sum_ = a.sum + x,
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squaresSum_ = a.squaresSum + (x * x);
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return {
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sum: sum_,
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squaresSum: squaresSum_,
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stages: a.stages.concat(
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Math.sqrt((squaresSum_ / n) - Math.pow((sum_ / n), 2))
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)
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};
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}, {
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sum: 0,
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squaresSum: 0,
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stages: []
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}).stages
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})([2, 4, 4, 4, 5, 5, 7, 9]);
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