[OpenVINO backend] Support numpy.isneginf (#21665)

* feat: included tests for isneginf

* feat: added isneginf to numpy openvino

* fix: code format with pre-commit

Author: samthakur587

keras/src/backend/openvino/excluded_concrete_tests.txt

@@ -36,7 +36,6 @@ NumpyDtypeTest::test_isfinite
 NumpyDtypeTest::test_isin
 NumpyDtypeTest::test_isinf
 NumpyDtypeTest::test_isnan
-NumpyDtypeTest::test_isneginf
 NumpyDtypeTest::test_isposinf
 NumpyDtypeTest::test_kron
 NumpyDtypeTest::test_linspace
@@ -94,7 +93,6 @@ NumpyOneInputOpsCorrectnessTest::test_floor_divide
 NumpyOneInputOpsCorrectnessTest::test_imag
 NumpyOneInputOpsCorrectnessTest::test_isfinite
 NumpyOneInputOpsCorrectnessTest::test_isinf
-NumpyOneInputOpsCorrectnessTest::test_isneginf
 NumpyOneInputOpsCorrectnessTest::test_isposinf
 NumpyOneInputOpsCorrectnessTest::test_max
 NumpyOneInputOpsCorrectnessTest::test_mean
@@ -156,12 +154,10 @@ NumpyOneInputOpsDynamicShapeTest::test_cbrt
 NumpyOneInputOpsDynamicShapeTest::test_corrcoef
 NumpyOneInputOpsDynamicShapeTest::test_hamming
 NumpyOneInputOpsDynamicShapeTest::test_hanning
-NumpyOneInputOpsDynamicShapeTest::test_isneginf
 NumpyOneInputOpsDynamicShapeTest::test_isposinf
 NumpyOneInputOpsDynamicShapeTest::test_kaiser
 NumpyOneInputOpsStaticShapeTest::test_angle
 NumpyOneInputOpsStaticShapeTest::test_cbrt
-NumpyOneInputOpsStaticShapeTest::test_isneginf
 NumpyOneInputOpsStaticShapeTest::test_isposinf
 NumpyTwoInputOpsDynamicShapeTest::test_gcd
 NumpyTwoInputOpsDynamicShapeTest::test_heaviside

keras/src/backend/openvino/numpy.py

@@ -969,9 +969,32 @@ def isnan(x):
 
 
 def isneginf(x):
-    raise NotImplementedError(
-        "`isneginf` is not supported with openvino backend"
-    )
+    x = get_ov_output(x)
+    x_type = x.get_element_type()
+
+    if x_type.is_integral() or x_type == Type.boolean:
+        shape = ov_opset.shape_of(x, "i32").output(0)
+        false_const = ov_opset.constant(False, Type.boolean).output(0)
+        return OpenVINOKerasTensor(
+            ov_opset.broadcast(false_const, shape).output(0)
+        )
+
+    if x_type == Type.bf16:
+        x_f32 = ov_opset.convert(x, Type.f32).output(0)
+        neg_inf = ov_opset.constant(-np.inf, Type.f32).output(0)
+        is_neg_inf = ov_opset.equal(x_f32, neg_inf).output(0)
+    else:
+        if x_type == Type.f16:
+            neg_inf = ov_opset.constant(-np.inf, Type.f16).output(0)
+        elif x_type == Type.f32:
+            neg_inf = ov_opset.constant(-np.inf, Type.f32).output(0)
+        elif x_type == Type.f64:
+            neg_inf = ov_opset.constant(-np.inf, Type.f64).output(0)
+        else:
+            neg_inf = ov_opset.constant(-np.inf, Type.f32).output(0)
+        is_neg_inf = ov_opset.equal(x, neg_inf).output(0)
+
+    return OpenVINOKerasTensor(is_neg_inf)
 
 
 def isposinf(x):