Random<>::SampleUniform() has inconsistant behaviours on CPU, GPU and docs
cairijun opened this issue · 1 comments
cairijun commented
According to docs, Random<>::SampleUniform(&dst, a, b) should generate random samples uniformly distributed in [a, b).
However, when DType = float, std::uniform_real_distribution, which is used internally in SampleUniform for CPU, might accidentally return b. This is an issue in most stdlib implementations. See LWG#2524, GCC#63176, LLVM#18767.
On GPU, curandGenerateUniform() is used, but it actually produces samples in (0, 1] according its documentation:
Results are 32-bit floating point values between 0.0f and 1.0f, excluding 0.0f and including 1.0f.
which results in (a, b] for SampleUniform(). The same issue affects double version as well.