Begin statistics creation

CHDataManagement/Workouts/File/RouteSample.swift

@@ -0,0 +1,95 @@
+
+struct RouteSample {
+
+    /// The x-coordinate in the map image (left to right) in the range [0,1]
+    var x: Double
+
+    /// The y-coordinate in the map image (top to bottom) in the range [0,1]
+    var y: Double
+
+    /// The timestamp of the sample in the range [0,1]
+    var time: Double
+
+    /// The distance of the sample in the range [0,1]
+    var distance: Double
+
+    /// The elevation of the sample in the range [0,1]
+    var elevation: Double
+
+    /// The speed of the sample in the range [0,1]
+    var speed: Double
+
+    /// The pace of the sample in the range [0,1]
+    var pace: Double
+
+    /// The heart rate of the sample in the range [0,1]
+    var hr: Double
+
+    /// The active energy rate of the sample in the range [0,1]
+    var energy: Double?
+}
+
+extension RouteSample: Codable {
+
+    func encode(to encoder: any Encoder) throws {
+        var container = encoder.container(keyedBy: CodingKeys.self)
+        try container.encode(x.rounded(decimals: 4), forKey: .x)
+        try container.encode(y.rounded(decimals: 4), forKey: .y)
+        try container.encode(time.rounded(decimals: 4), forKey: .time)
+        try container.encode(distance.rounded(decimals: 4), forKey: .distance)
+        try container.encode(elevation.rounded(decimals: 4), forKey: .elevation)
+        try container.encode(speed.rounded(decimals: 4), forKey: .speed)
+        try container.encode(pace.rounded(decimals: 4), forKey: .pace)
+        try container.encode(hr.rounded(decimals: 4), forKey: .hr)
+        try container.encodeIfPresent(energy?.rounded(decimals: 4), forKey: .energy)
+    }
+}
+
+extension RouteSample: Identifiable {
+
+    var id: Double { x }
+}
+
+extension RouteSample {
+
+    static var zero: RouteSample {
+        .init(x: 0, y: 0, time: 0, distance: 0, elevation: 0, speed: 0, pace: 0, hr: 0, energy: nil)
+    }
+}
+
+extension Collection where Element == RouteSample {
+
+    var averageSample: RouteSample {
+        guard var average = first else {
+            return .zero
+        }
+        var energySamples = average.energy == nil ? 0 : 1
+        for sample in dropFirst() {
+            average.x += sample.x
+            average.y += sample.y
+            average.time += sample.time
+            average.distance += sample.distance
+            average.elevation += sample.elevation
+            average.speed += sample.speed
+            average.pace += sample.pace
+            average.hr += sample.hr
+            if let energy = sample.energy {
+                average.energy = (average.energy ?? 0) + energy
+                energySamples += 1
+            }
+        }
+        let scale = 1 / Double(count)
+        average.x *= scale
+        average.y *= scale
+        average.time *= scale
+        average.distance *= scale
+        average.elevation *= scale
+        average.speed *= scale
+        average.pace *= scale
+        average.hr *= scale
+        if let energy = average.energy, energySamples > 0 {
+            average.energy = energy / Double(energySamples)
+        }
+        return average
+    }
+}