10 lines
251 B
JavaScript
10 lines
251 B
JavaScript
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Array.prototype.mean = function() {
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return !this.length ? 0
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: this.reduce(function(pre, cur, i) {
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return (pre * i + cur) / (i + 1);
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});
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}
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alert( [1,2,3,4,5].mean() ); // 3
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alert( [].mean() ); // 0
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