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tensorflow::ops::Substr

#include <string_ops.h>

Return substrings from Tensor of strings.

Summary

For each string in the input Tensor, creates a substring starting at index pos with a total length of len.

If len defines a substring that would extend beyond the length of the input string, then as many characters as possible are used.

If pos is negative or specifies a character index larger than any of the input strings, then an InvalidArgumentError is thrown.

pos and len must have the same shape, otherwise a ValueError is thrown on Op creation.

NOTE: Substr supports broadcasting up to two dimensions. More about broadcasting here

Examples

Using scalar pos and len:

input = [b'Hello', b'World']
position = 1
length = 3
output = [b'ell', b'orl']

Using pos and len with same shape as input:

input = [[b'ten', b'eleven', b'twelve'],
         [b'thirteen', b'fourteen', b'fifteen'],
         [b'sixteen', b'seventeen', b'eighteen']]
position = [[1, 2, 3],
            [1, 2, 3],
            [1, 2, 3]]
length =   [[2, 3, 4],
            [4, 3, 2],
            [5, 5, 5]]
output = [[b'en', b'eve', b'lve'],
          [b'hirt', b'urt', b'te'],
          [b'ixtee', b'vente', b'hteen']]

Broadcasting pos and len onto input:

input = [[b'ten', b'eleven', b'twelve'],
         [b'thirteen', b'fourteen', b'fifteen'],
         [b'sixteen', b'seventeen', b'eighteen'],
         [b'nineteen', b'twenty', b'twentyone']]
position = [1, 2, 3]
length =   [1, 2, 3]
output = [[b'e', b'ev', b'lve'],
          [b'h', b'ur', b'tee'],
          [b'i', b've', b'hte'],
          [b'i', b'en', b'nty']]

Broadcasting input onto pos and len:

input = b'thirteen'
position = [1, 5, 7]
length =   [3, 2, 1]
output = [b'hir', b'ee', b'n']

Arguments:

  • scope: A Scope object
  • input: Tensor of strings
  • pos: Scalar defining the position of first character in each substring
  • len: Scalar defining the number of characters to include in each substring

Returns:

Constructors and Destructors
Substr(const ::tensorflow::Scope & scope, ::tensorflow::Input input, ::tensorflow::Input pos, ::tensorflow::Input len)
Public attributes
output
Public functions
node() const
::tensorflow::Node *
operator::tensorflow::Input() const
operator::tensorflow::Output() const

Public attributes

output

::tensorflow::Output output

Public functions

Substr

 Substr(
  const ::tensorflow::Scope & scope,
  ::tensorflow::Input input,
  ::tensorflow::Input pos,
  ::tensorflow::Input len
)

node

::tensorflow::Node * node() const 

operator::tensorflow::Input

operator::tensorflow::Input() const 

operator::tensorflow::Output

operator::tensorflow::Output() const 

© 2018 The TensorFlow Authors. All rights reserved.
Licensed under the Creative Commons Attribution License 3.0.
Code samples licensed under the Apache 2.0 License.
https://www.tensorflow.org/api_docs/cc/class/tensorflow/ops/substr.html