15 lines
243 B
JavaScript
15 lines
243 B
JavaScript
export default function(polygon) {
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var i = -1,
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n = polygon.length,
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a,
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b = polygon[n - 1],
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area = 0;
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while (++i < n) {
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a = b;
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b = polygon[i];
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area += a[1] * b[0] - a[0] * b[1];
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}
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return area / 2;
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}
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