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Calculate percentage distribution of values
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| func calculatePercentageDistribution(ofValues inputValues: [Double]) -> [Double] { | |
| let totalValue = inputValues.reduce(0.0) { $0.0 + $0.1 } | |
| guard totalValue > 0 else { | |
| return Array<Double>(repeating: 0.0, count: inputValues.count) | |
| } | |
| var fractionSum: Double = 0.0 | |
| var percentArray = inputValues.map { value -> Double in | |
| let value = (value * 100.0) / totalValue | |
| let roundedValue = round(value) | |
| fractionSum += (value - roundedValue) | |
| return roundedValue / 100.0 | |
| } | |
| // Find an index of the last positive value to adjust it. | |
| var lastPositiveValueIndex = percentArray.count - 1 | |
| while lastPositiveValueIndex > 0, !(percentArray[lastPositiveValueIndex] > 0.0) { | |
| lastPositiveValueIndex -= 1 | |
| } | |
| // This adjustment is for the greater good. The last percent value will be incorrect (at max by 0.9999%). | |
| // But the sum of all array values will be 100% which is nice. | |
| percentArray[lastPositiveValueIndex] = percentArray[lastPositiveValueIndex] + round(fractionSum)/100.0 | |
| return percentArray | |
| } |
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