Help protect the Great Barrier Reef with TensorFlow on Kaggle

Pads sequences to the same length.

### Used in the notebooks

Used in the guide Used in the tutorials

This function transforms a list (of length `num_samples`) of sequences (lists of integers) into a 2D Numpy array of shape `(num_samples, num_timesteps)`. `num_timesteps` is either the `maxlen` argument if provided, or the length of the longest sequence in the list.

Sequences that are shorter than `num_timesteps` are padded with `value` until they are `num_timesteps` long.

Sequences longer than `num_timesteps` are truncated so that they fit the desired length.

The position where padding or truncation happens is determined by the arguments `padding` and `truncating`, respectively. Pre-padding or removing values from the beginning of the sequence is the default.

````sequence = [[1], [2, 3], [4, 5, 6]]`
`tf.keras.preprocessing.sequence.pad_sequences(sequence)`
`array([[0, 0, 1],`
`       [0, 2, 3],`
`       [4, 5, 6]], dtype=int32)`
```
````tf.keras.preprocessing.sequence.pad_sequences(sequence, value=-1)`
`array([[-1, -1,  1],`
`       [-1,  2,  3],`
`       [ 4,  5,  6]], dtype=int32)`
```
````tf.keras.preprocessing.sequence.pad_sequences(sequence, padding='post')`
`array([[1, 0, 0],`
`       [2, 3, 0],`
`       [4, 5, 6]], dtype=int32)`
```
````tf.keras.preprocessing.sequence.pad_sequences(sequence, maxlen=2)`
`array([[0, 1],`
`       [2, 3],`
`       [5, 6]], dtype=int32)`
```

`sequences` List of sequences (each sequence is a list of integers).
`maxlen` Optional Int, maximum length of all sequences. If not provided, sequences will be padded to the length of the longest individual sequence.
`dtype` (Optional, defaults to int32). Type of the output sequences. To pad sequences with variable length strings, you can use `object`.
`padding` String, 'pre' or 'post' (optional, defaults to 'pre'): pad either before or after each sequence.
`truncating` String, 'pre' or 'post' (optional, defaults to 'pre'): remove values from sequences larger than `maxlen`, either at the beginning or at the end of the sequences.
`value` Float or String, padding value. (Optional, defaults to 0.)

Numpy array with shape `(len(sequences), maxlen)`

`ValueError` In case of invalid values for `truncating` or `padding`, or in case of invalid shape for a `sequences` entry.

[{ "type": "thumb-down", "id": "missingTheInformationINeed", "label":"Missing the information I need" },{ "type": "thumb-down", "id": "tooComplicatedTooManySteps", "label":"Too complicated / too many steps" },{ "type": "thumb-down", "id": "outOfDate", "label":"Out of date" },{ "type": "thumb-down", "id": "samplesCodeIssue", "label":"Samples / code issue" },{ "type": "thumb-down", "id": "otherDown", "label":"Other" }]
[{ "type": "thumb-up", "id": "easyToUnderstand", "label":"Easy to understand" },{ "type": "thumb-up", "id": "solvedMyProblem", "label":"Solved my problem" },{ "type": "thumb-up", "id": "otherUp", "label":"Other" }]