percentile

percentile(matrix: any[] | Mat | Tensor, perc: number) : any[]

param matrix - an Array, Mat or Tensor.

param perc a number in the interval [0, 100]

returns any[] - an Array representing the percentile (all the numbers with index larger than perc% of the values)

The percentile of a construct, whether it be a function or in our case, matrix-like structures, is a number for where values in an Array below a certain percentage, namely, perc, fall below. For example, the 60th percentile is the number where below 60% of all the scores may be found. So if we had [1,2,3,4,5,6,7,8,9,10], the 60th percentile would be '6' and everything below it ([6,5,4,3,2,1]) Note that the percentile is similar to the quantile.

Hence, in this function, we return an Array that contains all the values below the percentile (including the percentile value). The function name can be misleading as the percentile is actually a parameter and we're returning an Array of numbers in that percentile range.

This aligns well with our modern concept of the word 'percentile'. For example the statement 'he scored in the 99th percentile in his exam' we understand to be the top 1%. This makes sense according to the definition we use, as his score is equal to or above 99% of other scores.