scripts/builtin/kmeansPredict.dml

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# Builtin function that does predictions based on a set of centroids provided.
#
# INPUT:
# -----------------------------------------------
# X     The input Matrix to do KMeans on.
# C     The input Centroids to map X onto.
# -----------------------------------------------
#
# OUTPUT:
# ------------------------------------------------------
# Y     The mapping of records to centroids
# ------------------------------------------------------

m_kmeansPredict = function(Matrix[Double] X, Matrix[Double] C)
  return (Matrix[Double] Y)
{
  D =  -2 * (X %*% t(C)) + t(rowSums(C^2));
  P = (D <= rowMins (D));
  Y = rowIndexMax(P);
}