Android Histogram using GraphView in Kotlin

Histogram.kt

//This method takes as parameters the bincount; which is the number of bins you want your histogram to have
//and your data in the form of a double array. 
//Based on this SO answer "https://stackoverflow.com/questions/10786465/how-to-generate-bins-for-histogram-using-apache-math-3-0-in-java"
private fun displayHistogram(binCount: Int, data: DoubleArray) {
        val histogram = DoubleArray(binCount)
        val distribution = org.apache.commons.math3.random.EmpiricalDistribution(binCount)
        distribution.load(data)
//Not sure what this variable K does to be honest.
        var k = 0
        for (stats in distribution.binStats) {
            histogram[k++] = stats.n.toDouble()
        }
//binSize is the length of the bin. For example a bin size could span from 1-5 
//We need to know this in order to calculate the x values of the histogram
        val binSize = (data.max()!!.toDouble() - data.min()!!.toDouble()) / binCount
//The size of the histogram is the number of bins and the value of histogram[] at i index is the frequency of numbers 
//within the interval represented by binSize.
//So for example, histogram[] at index 1 has a frequcny or value of 2 for the range or binsize of between 1-5 occured 4   
        for (i in 0 until histogram.size) {
            series2?.appendData(DataPoint(
              //x values
              generateHistogramXValues(data.min()!!.toDouble(), histogram.size, binSize)[i], 
              //y values are the frequnecy of numbers within our binsize
              histogram[i]
            ), false, histogram.count())
        }
    }

//Simply creates an x values double array that gives the x axis positin for each bin
    private fun generateHistogramXValues(min: Double, numberOfBIns: Int, binSize: Double): DoubleArray {
        //create new array    
        val xValuesArray = DoubleArray(numberOfBIns)
        //loop from zero to the number of bins you desier. so if 5 bins then 5    
        for (i in 0 until numberOfBIns) {
            //the first item in the array needs to be the first bin which is also the min of our data    
            if (i == 0){
                 //set initial value to the min of our data if array is empty    
                xValuesArray[i] = min
            }else{
                 //add to the previous value in the array by a specific interval which is our binsize   
                val previous = xValuesArray[i-1]
                xValuesArray[i] = previous+binSize
            }
        }    
        return xValuesArray
    }