[Keras Ops] Add Histogram Operation

[DavidLandup0]

This PR adds the keras.ops.histogram() operation to the source implementations and API.

Example Usage

JAX

import numpy as np
import os

os.environ["KERAS_BACKEND"] = "jax"
import keras

input_tensor = np.array([1, 2, 3, 4, 5])
keras.ops.histogram(input_tensor)

Outputs:

(Array([1., 0., 1., 0., 0., 1., 0., 1., 0., 1.], dtype=float32),
 Array([1. , 1.4, 1.8, 2.2, 2.6, 3. , 3.4, 3.8, 4.2, 4.6, 5. ], dtype=float32))

TensorFlow

import numpy as np
import os

os.environ["KERAS_BACKEND"] = "tensorflow"
import keras

input_tensor = np.array([1, 2, 3, 4, 5])
keras.ops.histogram(input_tensor)

Outputs:

(<tf.Tensor: shape=(10,), dtype=int64, numpy=array([1, 0, 1, 0, 0, 1, 0, 1, 0, 1])>,
 <tf.Tensor: shape=(11,), dtype=float64, numpy=array([1. , 1.4, 1.8, 2.2, 2.6, 3. , 3.4, 3.8, 4.2, 4.6, 5. ])>)

NumPy

import numpy as np
import os

os.environ["KERAS_BACKEND"] = "numpy"
import keras

input_tensor = np.array([1, 2, 3, 4, 5])
keras.ops.histogram(input_tensor)

Outputs:

(array([1, 0, 1, 0, 0, 1, 0, 1, 0, 1]),
 array([1. , 1.4, 1.8, 2.2, 2.6, 3. , 3.4, 3.8, 4.2, 4.6, 5. ]))

Torch

import numpy as np
import os

os.environ["KERAS_BACKEND"] = "torch"
import keras

input_tensor = np.array([1., 2., 3., 4., 5.])
keras.ops.histogram(input_tensor)

Outputs:

(tensor([1., 0., 1., 0., 0., 1., 0., 1., 0., 1.]),
 tensor([1.0000, 1.4000, 1.8000, 2.2000, 2.6000, 3.0000, 3.4000, 3.8000, 4.2000,
         4.6000, 5.0000]))

Notes

• The TensorFlow tf.histogram_fixed_width() and tf.histogram_fixed_width_bins() methods had different numerical behavior from PyTorch, NumPy and JAX, so the TensorFlow math module has its own implementation.

[fchollet]

Awesome -- thank you for the contribution!

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 72.88136% with 16 lines in your changes missing coverage. Please review.

Project coverage is 78.82%. Comparing base (084b7e1) to head (3a7b031).

Files with missing lines	Patch %	Lines
keras/src/ops/math.py	60.52%	11 Missing and 4 partials ⚠️
keras/api/_tf_keras/keras/ops/__init__.py	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #20316      +/-   ##
==========================================
- Coverage   78.83%   78.82%   -0.01%     
==========================================
  Files         512      512              
  Lines       48995    49054      +59     
  Branches     9021     9035      +14     
==========================================
+ Hits        38624    38667      +43     
- Misses       8509     8521      +12     
- Partials     1862     1866       +4     

Flag	Coverage Δ
keras	78.68% <72.88%> (-0.01%)	⬇️
keras-jax	62.27% <47.45%> (-0.02%)	⬇️
keras-numpy	57.42% <49.15%> (-0.01%)	⬇️
keras-tensorflow	63.56% <64.40%> (+<0.01%)	⬆️
keras-torch	62.26% <49.15%> (-0.02%)	⬇️

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