View source on GitHub |
Generates a tf.data.Dataset
from text files in a directory.
tf.keras.utils.text_dataset_from_directory(
directory, labels='inferred', label_mode='int',
class_names=None, batch_size=32, max_length=None, shuffle=True, seed=None,
validation_split=None, subset=None, follow_links=False
)
If your directory structure is:
main_directory/
...class_a/
......a_text_1.txt
......a_text_2.txt
...class_b/
......b_text_1.txt
......b_text_2.txt
Then calling text_dataset_from_directory(main_directory, labels='inferred')
will return a tf.data.Dataset
that yields batches of texts from
the subdirectories class_a
and class_b
, together with labels
0 and 1 (0 corresponding to class_a
and 1 corresponding to class_b
).
Only .txt
files are supported at this time.
Args | |
---|---|
directory
|
Directory where the data is located.
If labels is "inferred", it should contain
subdirectories, each containing text files for a class.
Otherwise, the directory structure is ignored.
|
labels
|
Either "inferred"
(labels are generated from the directory structure),
None (no labels),
or a list/tuple of integer labels of the same size as the number of
text files found in the directory. Labels should be sorted according
to the alphanumeric order of the text file paths
(obtained via os.walk(directory) in Python).
|
label_mode
|
|
class_names
|
Only valid if "labels" is "inferred". This is the explict list of class names (must match names of subdirectories). Used to control the order of the classes (otherwise alphanumerical order is used). |
batch_size
|
Size of the batches of data. Default: 32. |
max_length
|
Maximum size of a text string. Texts longer than this will
be truncated to max_length .
|
shuffle
|
Whether to shuffle the data. Default: True. If set to False, sorts the data in alphanumeric order. |
seed
|
Optional random seed for shuffling and transformations. |
validation_split
|
Optional float between 0 and 1, fraction of data to reserve for validation. |
subset
|
One of "training" or "validation".
Only used if validation_split is set.
|
follow_links
|
Whether to visits subdirectories pointed to by symlinks. Defaults to False. |
Returns | |
---|---|
A tf.data.Dataset object.
|
Rules regarding labels format:
- if
label_mode
isint
, the labels are anint32
tensor of shape(batch_size,)
. - if
label_mode
isbinary
, the labels are afloat32
tensor of 1s and 0s of shape(batch_size, 1)
. - if
label_mode
iscategorial
, the labels are afloat32
tensor of shape(batch_size, num_classes)
, representing a one-hot encoding of the class index.