Files
eigen/unsupported/test/cxx11_tensor_random.cpp
2026-03-08 16:19:48 -07:00

100 lines
3.1 KiB
C++

// This file is part of Eigen, a lightweight C++ template library
// for linear algebra.
//
// Copyright (C) 2014 Benoit Steiner <benoit.steiner.goog@gmail.com>
//
// This Source Code Form is subject to the terms of the Mozilla
// Public License v. 2.0. If a copy of the MPL was not distributed
// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
#include "main.h"
#include <Eigen/Tensor>
template <typename Scalar>
static void test_default() {
Tensor<Scalar, 1> vec(6);
// Fixme: we should check that the generated numbers follow a uniform
// distribution instead.
// For low-precision types (half, bfloat16), the RNG has limited distinct
// values (e.g. 128 for bfloat16), so adjacent collisions are possible.
// Retry a few times to avoid spurious failures.
bool all_distinct = false;
for (int attempt = 0; attempt < 10 && !all_distinct; ++attempt) {
vec.setRandom();
all_distinct = true;
for (int i = 1; i < 6; ++i) {
if (vec(i) == vec(i - 1)) {
all_distinct = false;
break;
}
}
}
VERIFY(all_distinct);
}
template <typename Scalar>
static void test_normal() {
Tensor<Scalar, 1> vec(6);
// Fixme: we should check that the generated numbers follow a gaussian
// distribution instead.
bool all_distinct = false;
for (int attempt = 0; attempt < 10 && !all_distinct; ++attempt) {
vec.template setRandom<Eigen::internal::NormalRandomGenerator<Scalar>>();
all_distinct = true;
for (int i = 1; i < 6; ++i) {
if (vec(i) == vec(i - 1)) {
all_distinct = false;
break;
}
}
}
VERIFY(all_distinct);
}
struct MyGenerator {
MyGenerator() {}
MyGenerator(const MyGenerator&) {}
// Return a random value to be used. "element_location" is the
// location of the entry to set in the tensor, it can typically
// be ignored.
int operator()(Eigen::DenseIndex element_location, Eigen::DenseIndex /*unused*/ = 0) const {
return static_cast<int>(3 * element_location);
}
// Same as above but generates several numbers at a time.
internal::packet_traits<int>::type packetOp(Eigen::DenseIndex packet_location,
Eigen::DenseIndex /*unused*/ = 0) const {
const int packetSize = internal::packet_traits<int>::size;
EIGEN_ALIGN_MAX int values[packetSize];
for (int i = 0; i < packetSize; ++i) {
values[i] = static_cast<int>(3 * (packet_location + i));
}
return internal::pload<typename internal::packet_traits<int>::type>(values);
}
};
static void test_custom() {
Tensor<int, 1> vec(6);
vec.setRandom<MyGenerator>();
for (int i = 0; i < 6; ++i) {
VERIFY_IS_EQUAL(vec(i), 3 * i);
}
}
EIGEN_DECLARE_TEST(cxx11_tensor_random) {
CALL_SUBTEST((test_default<float>()));
CALL_SUBTEST((test_normal<float>()));
CALL_SUBTEST((test_default<double>()));
CALL_SUBTEST((test_normal<double>()));
CALL_SUBTEST((test_default<Eigen::half>()));
CALL_SUBTEST((test_normal<Eigen::half>()));
CALL_SUBTEST((test_default<Eigen::bfloat16>()));
CALL_SUBTEST((test_normal<Eigen::bfloat16>()));
CALL_SUBTEST(test_custom());
}