Creates a Python Class that internally iterates over the data.

make_generator_from_dataframe(
  dt,
  x_cols = NULL,
  y_cols,
  x_transform = NULL,
  y_transform = NULL,
  generator = keras::image_data_generator(),
  batch_size = 32L,
  shuffle = TRUE,
  seed = 1L,
  y_cols_to_categorical = TRUE,
  subset = NULL,
  ignore_class_split = FALSE
)

Arguments

dt

data.frame|data.table
Data container to iterate over.

x_cols

character
Names of features to be used. Defaults to all but y_cols.

y_cols

character
Target variable. Automatically converted to one-hot if "y_cols_to_categorical" is TRUE.

x_transform

function
Function used to transform data to a keras input format for features.

y_transform

function
Function used to transform data to a keras input format for the response.

generator

Python Object
A generator as e.g. obtained from keras::image_data_generator. Used for consistent train-test splits.

batch_size

integer
Batch size.

shuffle

logical
Should data be shuffled?

seed

integer
Set a seed for shuffling data.

y_cols_to_categorical

logical
Should target be converted to one-hot representation?

subset

character
Should samples be generated from 'training' or 'validation' set? Only applicable together with a 'generator'.

ignore_class_split

logical
Test whether all class labels appear in all splits.