tf.transpose

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Transposes a, where a is a Tensor.

tf.transpose(
    a, perm=None, conjugate=False, name='transpose'
)

Permutes the dimensions according to the value of perm.

The returned tensor's dimension i will correspond to the input dimension perm[i]. If perm is not given, it is set to (n-1...0), where n is the rank of the input tensor. Hence by default, this operation performs a regular matrix transpose on 2-D input Tensors.

If conjugate is True and a.dtype is either complex64 or complex128 then the values of a are conjugated and transposed.

For example:

x = tf.constant([[1, 2, 3], [4, 5, 6]])
tf.transpose(x)
<tf.Tensor: shape=(3, 2), dtype=int32, numpy=
array([[1, 4],
       [2, 5],
       [3, 6]], dtype=int32)>

Equivalently, you could call tf.transpose(x, perm=[1, 0]).

If x is complex, setting conjugate=True gives the conjugate transpose:

x = tf.constant([[1 + 1j, 2 + 2j, 3 + 3j],
                 [4 + 4j, 5 + 5j, 6 + 6j]])
tf.transpose(x, conjugate=True)
<tf.Tensor: shape=(3, 2), dtype=complex128, numpy=
array([[1.-1.j, 4.-4.j],
       [2.-2.j, 5.-5.j],
       [3.-3.j, 6.-6.j]])>

'perm' is more useful for n-dimensional tensors where n > 2:

x = tf.constant([[[ 1,  2,  3],
                  [ 4,  5,  6]],
                 [[ 7,  8,  9],
                  [10, 11, 12]]])

As above, simply calling tf.transpose will default to perm=[2,1,0].

To take the transpose of the matrices in dimension-0 (such as when you are transposing matrices where 0 is the batch dimesnion), you would set perm=[0,2,1].

tf.transpose(x, perm=[0, 2, 1])
<tf.Tensor: shape=(2, 3, 2), dtype=int32, numpy=
array([[[ 1,  4],
        [ 2,  5],
        [ 3,  6]],
        [[ 7, 10],
        [ 8, 11],
        [ 9, 12]]], dtype=int32)>

Note: This has a shorthand linalg.matrix_transpose):

Args
a	A Tensor.
perm	A permutation of the dimensions of a. This should be a vector.
conjugate	Optional bool. Setting it to True is mathematically equivalent to tf.math.conj(tf.transpose(input)).
name	A name for the operation (optional).

Returns
A transposed Tensor.

Numpy Compatibility

In numpy transposes are memory-efficient constant time operations as they simply return a new view of the same data with adjusted strides.

TensorFlow does not support strides, so transpose returns a new tensor with the items permuted.