Add tf.signal.frame() op.

[Lewuathe]

Add frame op as provided in TensorFlow core. It's also needed to implement stft, istft ops to make slices of the sample.

See: tensorflow/tfjs#1362

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This change is 

[nsthorat]

Reviewable status: 0 of 1 approvals obtained (waiting on @Lewuathe)

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src/ops/signal_ops.ts, line 72 at r1 (raw file):

 * @doc {heading: 'Operations', subheading: 'Signal', namespace: 'signal'}
 */
function frame_(input: Tensor1D, frameLength: number,

s/input/signal

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src/ops/signal_ops.ts, line 73 at r1 (raw file):

 */
function frame_(input: Tensor1D, frameLength: number,
  frameStep: number): Tensor {

checking that you're using vscode and our autoformatter :)

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src/ops/signal_ops.ts, line 73 at r1 (raw file):

 */
function frame_(input: Tensor1D, frameLength: number,
  frameStep: number): Tensor {

can you add padEnd, padValue, and axis?

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src/ops/signal_ops.ts, line 85 at r1 (raw file):

  }

  return concat(output).as2D(output.length, frameLength);

output.concat

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src/ops/signal_ops_test.ts, line 89 at r1 (raw file):

  it('3 length frames with step 5', () => {
    const input = tf.tensor1d([1, 2, 3, 4, 5]);
    const output = tf.frame(input, 3, 5);

this should be tf.signal.frame

the export here needs to be changed to export * as signal:

https://github.com/tensorflow/tfjs-core/blob/master/src/ops/ops.ts#L47

[Lewuathe]

Reviewable status: 0 of 1 approvals obtained (waiting on @Lewuathe and @nsthorat)

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src/ops/signal_ops.ts, line 73 at r1 (raw file):

Previously, nsthorat (Nikhil Thorat) wrote…

can you add padEnd, padValue, and axis?

Okay, I'll try.

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src/ops/signal_ops.ts, line 85 at r1 (raw file):

Previously, nsthorat (Nikhil Thorat) wrote…

output.concat

Actually, the output is not tensor. As it's just an array of tensor, we can not call ops directly.

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src/ops/signal_ops_test.ts, line 89 at r1 (raw file):

Previously, nsthorat (Nikhil Thorat) wrote…

this should be tf.signal.frame

the export here needs to be changed to export * as signal:

https://github.com/tensorflow/tfjs-core/blob/master/src/ops/ops.ts#L47

Will do.

[nsthorat]

Reviewed 3 of 3 files at r2.
Reviewable status: complete! 1 of 1 approvals obtained (waiting on @Lewuathe)

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src/ops/signal_ops.ts, line 64 at r2 (raw file):

 *
 * ```js
 * tf.frame([1, 2, 3], 2, 1).print();

we just added a new CI that runs the snippets and checks for errors, this is failing now because you need to do tf.signal

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src/ops/signal_ops.ts, line 66 at r2 (raw file):

 * tf.frame([1, 2, 3], 2, 1).print();
 * ```
 * @param input The input tensor to be expanded

s/input/signal

[nsthorat]

See this for failures: https://pantheon.corp.google.com/cloud-build/builds/ecf44c74-fa85-4c83-ae90-7f42c9d0c603?project=learnjs-174218

[nsthorat]

Reviewable status: complete! 1 of 1 approvals obtained (waiting on @Lewuathe)

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src/ops/signal_ops_test.ts, line 105 at r2 (raw file):

    const output = tf.signal.frame(input, 6, 0);
    expect(output.shape).toEqual([0, 6]);
    expectArraysClose(output, []);

FYI Apologies for this but once this PR is in you will have to do .data(): #1716

[Lewuathe]

See this for failures: https://pantheon.corp.google.com/cloud-build/builds/ecf44c74-fa85-4c83-ae90-7f42c9d0c603?project=learnjs-174218

Thanks but unfortunately I do not have permission to look into that. But anyway, I guess the problem is fixed.

[nsthorat]

Ah apologies that's the internal version of the link, you can see the failure by clicking details:

[nsthorat]

Ah looks like we may have a bug, I think this will fix it: #1737

[nsthorat]

Thanks for the awesome PR as always @Lewuathe :)