correlation method

num correlation(
  1. NumericColumn that
)

The correlation between the values stored in this and those in that.

Implementation

num correlation(NumericColumn that) {
  if (that.length != length) {
    throw PackhorseError.badStructure(
        "Correlation between columns with different lengths.");
  }
  final thisVector = NumericColumn(zScores),
      thatVector = NumericColumn(that.zScores);
  return thisVector.dot(thatVector);
}