-- given some images return a classifier
-- or nothing if the number of images does not match the number of labels
trainClassifier :: [ImageMatrix] -> [Label] -> Maybe (ImageMatrix -> Label)
trainClassifier images labels = if length images == length labels then
    Just randomClassifier
  else
    Nothing
trainClassifier :: [ImageMatrix] -> [Label] -> Maybe (ImageMatrix -> Label)
trainClassifier images labels = if length images == length labels then
    Just randomClassifier
  else
    Nothing
trainClassifier images labels = if length images == length labels then
    Just randomClassifier
  else
    Nothing