RosettaCodeData/Task/Text-processing-1/Swift/text-processing-1.swift

81 lines
2.0 KiB
Swift

import Foundation
let fmtDbl = { String(format: "%10.3f", $0) }
Task.detached {
let formatter = DateFormatter()
formatter.dateFormat = "yyyy-MM-dd"
let (data, _) = try await URLSession.shared.bytes(from: URL(fileURLWithPath: CommandLine.arguments[1]))
var rowStats = [(Date, Double, Int)]()
var invalidPeriods = 0
var invalidStart: Date?
var sumFile = 0.0
var readings = 0
var longestInvalid = 0
var longestInvalidStart: Date?
var longestInvalidEnd: Date?
for try await line in data.lines {
let lineSplit = line.components(separatedBy: "\t")
guard !lineSplit.isEmpty, let date = formatter.date(from: lineSplit[0]) else {
fatalError("Invalid date \(lineSplit[0])")
}
let data = Array(lineSplit.dropFirst())
let parsed = stride(from: 0, to: data.endIndex, by: 2).map({idx -> (Double, Int) in
let slice = data[idx..<idx+2]
return (Double(slice[idx]) ?? 0, Int(slice[idx+1]) ?? 0)
})
var sum = 0.0
var numValid = 0
for (val, flag) in parsed {
if flag <= 0 {
if invalidStart == nil {
invalidStart = date
}
invalidPeriods += 1
} else {
if invalidPeriods > longestInvalid {
longestInvalid = invalidPeriods
longestInvalidStart = invalidStart
longestInvalidEnd = date
}
sumFile += val
sum += val
numValid += 1
readings += 1
invalidPeriods = 0
invalidStart = nil
}
}
if numValid != 0 {
rowStats.append((date, sum / Double(numValid), parsed.count - numValid))
}
}
for stat in rowStats.lazy.reversed().prefix(5) {
print("\(stat.0): Average: \(fmtDbl(stat.1)); Valid Readings: \(24 - stat.2); Invalid Readings: \(stat.2)")
}
print("""
Sum File: \(fmtDbl(sumFile))
Average: \(fmtDbl(sumFile / Double(readings)))
Readings: \(readings)
Longest Invalid: \(longestInvalid) (\(longestInvalidStart!) - \(longestInvalidEnd!))
""")
exit(0)
}
dispatchMain()