Moving Average

077_moving_average.cell

// ============================================================================
// 077 — Moving Average
// ============================================================================
// Compute a simple moving average over a series of values.
//
// Run:   soma run 077_moving_average.cell run
// Expect:
//   Values: [10, 20, 30, 40, 50, 60, 70, 80, 90, 100]
//   3-period moving averages:
//   Period 3: avg = 20
//   Period 4: avg = 30
//   Period 5: avg = 40
//   Period 6: avg = 50
//   Period 7: avg = 60
//   Period 8: avg = 70
//   Period 9: avg = 80
//   Period 10: avg = 90

cell MovingAverage {

    on run() {
        let values = list(10, 20, 30, 40, 50, 60, 70, 80, 90, 100)
        print("Values: {values}")

        let window = 3
        print("{window}-period moving averages:")

        // Compute moving average using enumerate
        let indexed = enumerate(values)
        let count = values.length

        let i = window - 1
        while i < count {
            // Sum the window
            let sum = 0
            let j = i - window + 1
            while j <= i {
                // Access element by iterating
                let idx = 0
                for v in values {
                    if idx == j {
                        sum = sum + v
                    }
                    idx = idx + 1
                }
                j = j + 1
            }
            let avg = sum / window
            let period = i + 1
            print("Period {period}: avg = {avg}")
            i = i + 1
        }

        return "done"
    }
}