【Complex op】add complex support for numel (#56412)

* add complex numel

* change test && add doc

paddle/phi/kernels/cpu/numel_kernel.cc

@@ -30,7 +30,9 @@ PD_REGISTER_KERNEL(numel,
                    phi::dtype::bfloat16,
                    float,
                    double,
-                   bool) {
+                   bool,
+                   phi::dtype::complex<float>,
+                   phi::dtype::complex<double>) {
   kernel->OutputAt(0).SetDataType(phi::DataType::INT64);
 }
 
@@ -47,7 +49,9 @@ PD_REGISTER_KERNEL(numel,
                    phi::dtype::bfloat16,
                    float,
                    double,
-                   bool) {
+                   bool,
+                   phi::dtype::complex<float>,
+                   phi::dtype::complex<double>) {
   kernel->OutputAt(0).SetDataType(phi::DataType::INT64);
 }
 #endif

paddle/phi/kernels/gpu/numel_kernel.cu

@@ -29,6 +29,8 @@ PD_REGISTER_KERNEL(numel,
                    phi::dtype::bfloat16,
                    float,
                    double,
-                   bool) {
+                   bool,
+                   phi::dtype::complex<float>,
+                   phi::dtype::complex<double>) {
   kernel->OutputAt(0).SetDataType(phi::DataType::INT64);
 }

paddle/phi/kernels/xpu/numel_kernel.cc

@@ -27,6 +27,8 @@ PD_REGISTER_KERNEL(numel,
                    int64_t,
                    phi::dtype::float16,
                    float,
-                   bool) {
+                   bool,
+                   phi::dtype::complex<float>,
+                   phi::dtype::complex<double>) {
   kernel->OutputAt(0).SetDataType(phi::DataType::INT64);
 }

python/paddle/tensor/stat.py

@@ -227,7 +227,7 @@ def numel(x, name=None):
     Returns the number of elements for a tensor, which is a 0-D int64 Tensor with shape [].
 
     Args:
-        x (Tensor): The input Tensor, it's data type can be bool, float16, float32, float64, int32, int64.
+        x (Tensor): The input Tensor, it's data type can be bool, float16, float32, float64, int32, int64, complex64, complex128.
         name (str, optional): Name for the operation (optional, default is None).
             For more information, please refer to :ref:`api_guide_Name`.
 

test/legacy_test/test_numel_op.py

@@ -71,6 +71,54 @@ class TestNumelOp2FP16(TestNumelOp):
         self.shape = (0,)
 
 
+class TestNumelOpComplex(TestNumelOp):
+    def setUp(self):
+        self.op_type = "size"
+        self.python_api = paddle.numel
+        self.init()
+        x = np.random.random(self.shape).astype(
+            self.dtype
+        ) + 1j * np.random.random(self.shape).astype(self.dtype)
+        self.inputs = {
+            'Input': x,
+        }
+        self.outputs = {'Out': np.array(np.size(x))}
+
+    def init(self):
+        self.dtype = np.complex64
+        self.shape = (6, 56, 8, 55)
+
+
+class Test1NumelOpComplex64(TestNumelOpComplex):
+    def init(self):
+        self.dtype = np.complex64
+        self.shape = (11, 66)
+
+
+class Test2NumelOpComplex64(TestNumelOpComplex):
+    def init(self):
+        self.dtype = np.complex64
+        self.shape = (0,)
+
+
+class Test0NumelOpComplex128(TestNumelOpComplex):
+    def init(self):
+        self.dtype = np.complex128
+        self.shape = (6, 56, 8, 55)
+
+
+class Test1NumelOpComplex128(TestNumelOpComplex):
+    def init(self):
+        self.dtype = np.complex128
+        self.shape = (11, 66)
+
+
+class Test2NumelOpComple128(TestNumelOpComplex):
+    def init(self):
+        self.dtype = np.complex128
+        self.shape = (0,)
+
+
 @unittest.skipIf(
     not core.is_compiled_with_cuda()
     or not core.is_bfloat16_supported(core.CUDAPlace(0)),