Kotlin Expanding Mean

emean.kt

//An expanding mean function created as my own implementation of pandas' .expanding(window).mean()
//Only thing missing is the window size option.

fun expandingMean (data: List<Float>): MutableList<Float> {
    var result = mutableListOf<Float>()
    var i = 0
    for (value in data.listIterator()) {
        result.add(data.slice(0..i).average().toFloat())
        i += 1
    }
    return result
}

fun main (args: Array<String>) {
    val arr = mutableListOf<Float>()
    for (i in 1..25) {
        arr.add(i.toFloat())
    }
    val em = expandingMean(arr)
    print("$em")
}

//input a range of floats 1-25 (inclusive)
//output is [1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, 5.0, 5.5, 6.0, 6.5, 7.0, 7.5, 8.0, 8.5, 9.0, 9.5, 10.0, 10.5, 11.0, 11.5, 12.0, 12.5, 13.0]