safemin.tcc (ulmblas/impl/lapack/safemin.tcc)

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#ifndef ULMBLAS_IMPL_LAPACK_SAFEMIN_TCC

#define ULMBLAS_IMPL_LAPACK_SAFEMIN_TCC 1

#include <limits>

#include <ulmblas/impl/lapack/safemin.h>

namespace ulmBLAS {

template <typename T>

T

safeMin()

{

    const T eps   = std::numeric_limits<T>::epsilon() * 0.5;

    const T small = T(1) / std::numeric_limits<T>::max();

    T sMin  = std::numeric_limits<T>::min();

    if (small>=sMin) {

//

//      Use SMALL plus a bit, to avoid the possibility of rounding

//      causing overflow when computing  1/sfmin.

//

        sMin = small*(1.0+eps);

    }

    return sMin;

}

} // namespace ulmBLAS

#endif // ULMBLAS_IMPL_LAPACK_SAFEMIN_TCC