Add OpenVINO backend support for argmin and argmax (keras-team#21060)

* Update numpy.py

* Update excluded_concrete_tests.txt

* all issues fixed

* Update numpy.py

* numpy.py reformatted

* Update excluded_concrete_tests.txt

* Update excluded_concrete_tests.txt

* Update excluded_concrete_tests.txt

* Update excluded_concrete_tests.txt

* Update excluded_concrete_tests.txt

* Update excluded_concrete_tests.txt

Author: Hmm-1224

keras/src/backend/openvino/excluded_concrete_tests.txt

@@ -5,8 +5,6 @@ NumpyDtypeTest::test_absolute_bool
 NumpyDtypeTest::test_add_
 NumpyDtypeTest::test_all
 NumpyDtypeTest::test_any
-NumpyDtypeTest::test_argmax
-NumpyDtypeTest::test_argmin
 NumpyDtypeTest::test_argpartition
 NumpyDtypeTest::test_array
 NumpyDtypeTest::test_bitwise
@@ -77,8 +75,6 @@ NumpyDtypeTest::test_square_bool
 HistogramTest
 NumpyOneInputOpsCorrectnessTest::test_all
 NumpyOneInputOpsCorrectnessTest::test_any
-NumpyOneInputOpsCorrectnessTest::test_argmax
-NumpyOneInputOpsCorrectnessTest::test_argmin
 NumpyOneInputOpsCorrectnessTest::test_argpartition
 NumpyOneInputOpsCorrectnessTest::test_array
 NumpyOneInputOpsCorrectnessTest::test_bitwise_invert
@@ -161,4 +157,4 @@ NumpyTwoInputOpsCorrectnessTest::test_quantile
 NumpyTwoInputOpsCorrectnessTest::test_take_along_axis
 NumpyTwoInputOpsCorrectnessTest::test_tensordot
 NumpyTwoInputOpsCorrectnessTest::test_vdot
-NumpyTwoInputOpsCorrectnessTest::test_where
+NumpyTwoInputOpsCorrectnessTest::test_where

keras/src/backend/openvino/numpy.py

@@ -328,11 +328,67 @@ def arctanh(x):
 
 
 def argmax(x, axis=None, keepdims=False):
-    raise NotImplementedError("`argmax` is not supported with openvino backend")
+    x = get_ov_output(x)
+    x_shape = x.get_partial_shape()
+    rank = x_shape.rank.get_length()
+    if rank == 0:
+        return OpenVINOKerasTensor(ov_opset.constant([0], Type.i32).output(0))
+    if axis is None:
+        flatten_shape = ov_opset.constant(
+            [-1] + [1] * (rank - 1), Type.i32
+        ).output(0)
+        x = ov_opset.reshape(x, flatten_shape, False).output(0)
+        axis = 0
+        k = ov_opset.constant(1, Type.i32).output(0)
+    else:
+        if axis < 0:
+            axis = rank + axis
+        k = ov_opset.constant(1, Type.i32).output(0)
+    topk_outputs = ov_opset.topk(
+        x,
+        k=k,
+        axis=axis,
+        mode="max",
+        sort="value",
+        stable=True,
+        index_element_type=Type.i32,
+    )
+    topk_indices = topk_outputs.output(1)
+    if not keepdims:
+        topk_indices = ov_opset.squeeze(topk_indices, [axis]).output(0)
+    return OpenVINOKerasTensor(topk_indices)
 
 
 def argmin(x, axis=None, keepdims=False):
-    raise NotImplementedError("`argmin` is not supported with openvino backend")
+    x = get_ov_output(x)
+    x_shape = x.get_partial_shape()
+    rank = x_shape.rank.get_length()
+    if rank == 0:
+        return OpenVINOKerasTensor(ov_opset.constant([0], Type.i32).output(0))
+    if axis is None:
+        flatten_shape = ov_opset.constant(
+            [-1] + [1] * (rank - 1), Type.i32
+        ).output(0)
+        x = ov_opset.reshape(x, flatten_shape, False).output(0)
+        axis = 0
+        k = ov_opset.constant(1, Type.i32).output(0)
+    else:
+        if axis < 0:
+            axis = rank + axis
+        k = ov_opset.constant(1, Type.i32).output(0)
+    topk_outputs = ov_opset.topk(
+        x,
+        k=k,
+        axis=axis,
+        mode="min",
+        sort="value",
+        stable=True,
+        index_element_type=Type.i32,
+    )
+    topk_indices = topk_outputs.output(1)
+    if not keepdims:
+        topk_indices = ov_opset.squeeze(topk_indices, [axis]).output(0)
+    return OpenVINOKerasTensor(topk_indices)
 
 
 def argsort(x, axis=-1):