fstatistic in breeze/scala

fstat.scala

import breeze.linalg._
import breeze.stats._
import breeze.numerics._

def fStatistic(test: DenseVector[Double], control: DenseMatrix[Double]): Double = {
  val mtest = test.toDenseMatrix
  val allData = DenseMatrix.vertcat(mtest, control)
  val grandMean = mean(allData)

  val testMean = mean(test)

  // sum of squares between canary mean and grandMean
  val sumSqBetwn: Double =
    sum(pow((testMean -:- grandMean), 2.0) *:* allData.rows.toDouble)

  // sum of squares total
  val sumSqTotal: Double = sum(pow(allData -:- grandMean, 2.0))

  // sum of squares error
  val sumSqError: Double = sumSqTotal - sumSqBetwn

  // mean square between
  val meanSqBtwn: Double = sumSqBetwn / (allData.cols - 1)

  // mean square within
  val meanSqWithin: Double = sumSqError / ((allData.rows * allData.cols) - mtest.cols).toDouble

  meanSqBtwn / meanSqWithin
}