scripts/builtin/l2svmPredict.dml

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# Builtin function Implements binary-class SVM with squared slack variables.
#
# INPUT:
# -----------------------------------------------------------------------------------
# X        matrix X of feature vectors to classify
# W        matrix of the trained variables
# verbose  Set to true if one wants print statements.
# -----------------------------------------------------------------------------------
#
# OUTPUT:
# ----------------------------------------------------------------------------------------
# YRaw  Classification Labels Raw, meaning not modified to clean
#       labels of 1's and -1's
# Y     Classification Labels Maxed to ones and zeros.
# ----------------------------------------------------------------------------------------

m_l2svmPredict = function(Matrix[Double] X, Matrix[Double] W, Boolean verbose = FALSE)
  return(Matrix[Double] YRaw, Matrix[Double] Y)
{
  n = nrow(X)
  m = ncol(X)
  wn = nrow(W)
  wm = ncol(W)
  if(m != wn){
    # If intercept was enabled
    if(m + 1 != wn){
      stop("l2svm Predict: Invalid shape of W [" +
        wm + "," + wn + "] or X [" + m + "," + n + "]")
    }
    # We could append a 1 column to X and multiply
    # But slicing W seems faster.
    YRaw = X %*% W[1:m,] + W[m+1,]
  }
  else{
    # If intercept was disabled
    YRaw = X %*% W
  }
  # Predict Y.
  Y = rowIndexMax(YRaw)
}