scripts/builtin/ffPredict.dml

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# This builtin function makes prediction given data and trained feedforward neural network model
#
# INPUT:
# --------------------------------------------------------------------------------------------
# Model       Trained ff neural network model
# X           Data used for making predictions
# batch_size  Batch size
# --------------------------------------------------------------------------------------------
#
# OUTPUT:
# ---------------------------------------------------------------------------------------
# pred   Predicted value
# ---------------------------------------------------------------------------------------

source("nn/layers/feedForward.dml") as ff_pass

s_ffPredict = function(List[unknown] model, Matrix[Double] X, Integer batch_size = 128) 
  return (Matrix[Double] pred) {
  
  rows = nrow(X)
  out = as.matrix(model["W2"])
  cols = ncol(out)
  pred = matrix(0, rows, cols)
  
  iters = ceil(rows / batch_size)

  batch = batch_size
  for(i in 1:iters) {
    begin = (i-1)*batch+1
    end = min(rows, begin + batch - 1)
    X_batch = X[begin:end,]
    output = ff_pass::feedForward(X_batch, model, TRUE)
    pred[begin:end,] = as.matrix(output[length(output)])
  }
}