58 lines
1.1 KiB
ReStructuredText
58 lines
1.1 KiB
ReStructuredText
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.. _libcudacxx-extended-api-math-isqrt:
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``cuda::isqrt``
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====================================
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Defined in the ``<cuda/cmath>`` header.
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.. code:: cuda
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namespace cuda {
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template <typename T>
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[[nodiscard]] __host__ __device__ constexpr
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T isqrt(T value) noexcept;
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} // namespace cuda
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The function computes the integer square root of the input value rounded down.
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**Parameters**
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- ``value``: The input value.
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**Return value**
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- The square root value of the input value rounded down.
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**Constraints**
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- ``T`` is an integer type.
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**Preconditions**
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- ``value`` is non-negative.
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Example
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-------
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.. code:: cuda
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#include <cuda/cmath>
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#include <cuda/std/cassert>
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__global__ void isqrt_kernel() {
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assert(cuda::isqrt(1) == 1);
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assert(cuda::isqrt(4) == 2);
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assert(cuda::isqrt(42) == 6);
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assert(cuda::isqrt(99) == 9);
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assert(cuda::isqrt(100) == 10);
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}
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int main() {
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isqrt_kernel<<<1, 1>>>();
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cudaDeviceSynchronize();
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}
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`See it on Godbolt 🔗 <https://godbolt.org/z/xPcj35dq6>`__
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