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Move multi_variable_gaussian_decomposition_method to a new
random_types.hpp header file.

cpp/include/raft/random/detail/multi_variable_gaussian.cuh

@@ -16,6 +16,7 @@
 
 #pragma once
 #include "curand_wrappers.hpp"
+#include "random_types.hpp"
 #include <cmath>
 #include <memory>
 #include <optional>
@@ -291,8 +292,6 @@ class multi_variable_gaussian_impl {
   ~multi_variable_gaussian_impl() { deinit(); }
 };  // end of multi_variable_gaussian_impl
 
-enum class multi_variable_gaussian_decomposition_method { CHOLESKY, JACOBI, QR };
-
 template <typename ValueType>
 class multi_variable_gaussian_setup_token;
 

cpp/include/raft/random/detail/random_types.hpp

@@ -0,0 +1,23 @@
+/*
+ * Copyright (c) 2018-2022, NVIDIA CORPORATION.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+namespace raft::random::detail {
+
+enum class multi_variable_gaussian_decomposition_method { CHOLESKY, JACOBI, QR };
+
+};  // end of namespace raft::random::detail