org.tensorflow.op.linalg

Class BandPart<T>

java.lang.Object

org.tensorflow.op.PrimitiveOp

org.tensorflow.op.linalg.BandPart<T>

Type Parameters:

T - data type for band() output

All Implemented Interfaces:

Op, Operand<T>

@Operator(group="linalg")
public final class BandPart<T>
extends PrimitiveOp
implements Operand<T>

Copy a tensor setting everything outside a central band in each innermost matrix

to zero.

The `band` part is computed as follows: Assume `input` has `k` dimensions `[I, J, K, ..., M, N]`, then the output is a tensor with the same shape where

`band[i, j, k, ..., m, n] = in_band(m, n) * input[i, j, k, ..., m, n]`.

The indicator function

`in_band(m, n) = (num_lower < 0 || (m-n) <= num_lower)) && (num_upper < 0 || (n-m) <= num_upper)`.

For example:

 # if 'input' is [[ 0,  1,  2, 3]
                  [-1,  0,  1, 2]
                  [-2, -1,  0, 1]
                  [-3, -2, -1, 0]],
 
 tf.matrix_band_part(input, 1, -1) ==> [[ 0,  1,  2, 3]
                                        [-1,  0,  1, 2]
                                        [ 0, -1,  0, 1]
                                        [ 0,  0, -1, 0]],
 
 tf.matrix_band_part(input, 2, 1) ==> [[ 0,  1,  0, 0]
                                       [-1,  0,  1, 0]
                                       [-2, -1,  0, 1]
                                       [ 0, -2, -1, 0]]
 

Useful special cases:

  tf.matrix_band_part(input, 0, -1) ==> Upper triangular part.
  tf.matrix_band_part(input, -1, 0) ==> Lower triangular part.
  tf.matrix_band_part(input, 0, 0) ==> Diagonal.
 

Field Summary

Fields inherited from class org.tensorflow.op.PrimitiveOp

operation

Method Summary

Modifier and Type	Method and Description
Output<T>	asOutput() Returns the symbolic handle of a tensor.
Output<T>	band() Rank `k` tensor of the same shape as input.
static <T,U extends Number> BandPart<T>	create(Scope scope, Operand<T> input, Operand<U> numLower, Operand<U> numUpper) Factory method to create a class wrapping a new BandPart operation.

Methods inherited from class org.tensorflow.op.PrimitiveOp

equals, hashCode, op, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Method Detail

create

public static <T,U extends Number> BandPart<T> create(Scope scope,
                                                      Operand<T> input,
                                                      Operand<U> numLower,
                                                      Operand<U> numUpper)

Factory method to create a class wrapping a new BandPart operation.

Parameters:

scope - current scope

input - Rank `k` tensor.

numLower - 0-D tensor. Number of subdiagonals to keep. If negative, keep entire lower triangle.

numUpper - 0-D tensor. Number of superdiagonals to keep. If negative, keep entire upper triangle.

Returns:

a new instance of BandPart

band

public Output<T> band()

Rank `k` tensor of the same shape as input. The extracted banded tensor.

asOutput

public Output<T> asOutput()

Description copied from interface: Operand

Returns the symbolic handle of a tensor.

Inputs to TensorFlow operations are outputs of another TensorFlow operation. This method is used to obtain a symbolic handle that represents the computation of the input.

Specified by:

asOutput in interface Operand<T>

See Also:

OperationBuilder.addInput(Output)