[JAX]: Support jax.lax.select_n operation for JAX (#28025)

**Overview:**
This pull request fixes #26570.

**Testing:**
- Tested the updated code.
- Verified that other functionalities remain unaffected.
![Screenshot from 2024-12-12
00-09-17](https://github.com/user-attachments/assets/ae118efa-2047-4bac-a90d-8318396e5f63)

**Dependencies:**
- No dependencies on other pull requests.

**CC:**
- @rkazants

---------

Signed-off-by: 11happy <soni5happy@gmail.com>
Co-authored-by: Roman Kazantsev <roman.kazantsev@intel.com>

Author: 11happy

src/frontends/jax/src/op/select_n.cpp

@@ -0,0 +1,46 @@
+// Copyright (C) 2018-2024 Intel Corporation
+// SPDX-License-Identifier: Apache-2.0
+//
+
+#include "openvino/frontend/jax/node_context.hpp"
+#include "openvino/op/concat.hpp"
+#include "openvino/op/constant.hpp"
+#include "openvino/op/convert.hpp"
+#include "openvino/op/gather_elements.hpp"
+#include "openvino/op/unsqueeze.hpp"
+#include "utils.hpp"
+
+using namespace ov::op;
+
+namespace ov {
+namespace frontend {
+namespace jax {
+namespace op {
+
+OutputVector translate_select_n(const NodeContext& context) {
+    num_inputs_check(context, 2);
+    auto num_inputs = static_cast<int>(context.get_input_size());
+    Output<Node> which = context.get_input(0);
+    if (which.get_element_type() == element::boolean) {
+        which = std::make_shared<v0::Convert>(which, element::i32);
+    }
+    auto const_axis = ov::op::v0::Constant::create(element::i64, Shape{1}, std::vector<int64_t>{0});
+    OutputVector unsqueezed_cases(num_inputs - 1);
+    unsqueezed_cases.reserve(num_inputs - 1);
+    for (int ind = 1; ind < num_inputs; ++ind) {
+        auto case_input = context.get_input(ind);
+        auto unsqueeze = std::make_shared<v0::Unsqueeze>(case_input, const_axis);
+        unsqueezed_cases[ind - 1] = unsqueeze;
+    }
+    Output<Node> cases = std::make_shared<v0::Concat>(unsqueezed_cases, 0);
+    which =
+        std::make_shared<v0::Unsqueeze>(which,
+                                        ov::op::v0::Constant::create(element::i64, Shape{1}, std::vector<int64_t>{0}));
+    Output<Node> result = std::make_shared<v6::GatherElements>(cases, which, 0);
+    return {result};
+};
+
+}  // namespace op
+}  // namespace jax
+}  // namespace frontend
+}  // namespace ov

src/frontends/jax/src/op_table.cpp

@@ -52,6 +52,7 @@ OP_CONVERTER(translate_reduce_window_max);
 OP_CONVERTER(translate_reduce_window_sum);
 OP_CONVERTER(translate_reshape);
 OP_CONVERTER(translate_rsqrt);
+OP_CONVERTER(translate_select_n);
 OP_CONVERTER(translate_slice);
 OP_CONVERTER(translate_square);
 OP_CONVERTER(translate_squeeze);
@@ -92,6 +93,7 @@ const std::map<std::string, CreatorFunction> get_supported_ops_jaxpr() {
             {"transpose", op::translate_transpose},
             {"rsqrt", op::translate_rsqrt},
             {"reshape", op::translate_reshape},
+            {"select_n", op::translate_select_n},
             {"slice", op::translate_slice},
             {"square", op::translate_square},
             {"sqrt", op::translate_1to1_match_1_input<v0::Sqrt>},

tests/layer_tests/jax_tests/test_select_n.py

@@ -0,0 +1,45 @@
+# Copyright (C) 2018-2024 Intel Corporation
+# SPDX-License-Identifier: Apache-2.0
+
+import jax
+import numpy as np
+import pytest
+from jax import numpy as jnp
+
+from jax_layer_test_class import JaxLayerTest
+
+rng = np.random.default_rng(5402)
+
+
+class TestSelectN(JaxLayerTest):
+    def _prepare_input(self):
+        cases = []
+        if (self.case_num == 2):
+            which = rng.choice([True, False], self.input_shape)
+        else:
+            which = rng.uniform(0, self.case_num, self.input_shape).astype(self.input_type)
+        which = np.array(which)
+        for i in range(self.case_num):
+            cases.append(jnp.array(np.random.uniform(-1000, 1000, self.input_shape).astype(self.input_type)))
+        cases = np.array(cases)
+        return (which, cases)
+
+    def create_model(self, input_shape, input_type, case_num):
+        self.input_shape = input_shape
+        self.input_type = input_type
+        self.case_num = case_num
+
+        def jax_select_n(which, cases):
+            return jax.lax.select_n(which, *cases)
+
+        return jax_select_n, None, 'select_n'
+
+    @pytest.mark.parametrize("input_shape", [[], [1], [2, 3], [4, 5, 6], [7, 8, 9, 10]])
+    @pytest.mark.parametrize("input_type", [np.int32, np.int64])
+    @pytest.mark.parametrize("case_num", [2, 3, 4])
+    @pytest.mark.nightly
+    @pytest.mark.precommit_jax_fe
+    def test_select_n(self, ie_device, precision, ir_version, input_shape, input_type, case_num):
+        self._test(*self.create_model(input_shape, input_type, case_num),
+                   ie_device, precision,
+                   ir_version)