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#include <Teuchos_BLAS.hpp>
Public Types | |
typedef ScalarType | c_type |
Public Member Functions | |
void | ROTG (ScalarType *da, ScalarType *db, ScalarType *c, ScalarType *s) const |
ScalarType | SIGN (const ScalarType &x, const ScalarType &y) const |
Definition at line 286 of file Teuchos_BLAS.hpp.
typedef ScalarType Teuchos::details::GivensRotator< ScalarType, false >::c_type |
Definition at line 288 of file Teuchos_BLAS.hpp.
void Teuchos::details::GivensRotator< ScalarType, false >::ROTG | ( | ScalarType * | da, |
ScalarType * | db, | ||
ScalarType * | c, | ||
ScalarType * | s | ||
) | const |
Definition at line 398 of file Teuchos_BLAS.hpp.
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inline |
Return ABS(x) if y > 0 or y is +0, else -ABS(x) (if y is -0 or < 0).
Note that SIGN respects IEEE 754 floating-point signed zero. This is a hopefully correct implementation of the Fortran type-generic SIGN intrinsic. ROTG for complex arithmetic doesn't require this function. C99 provides a copysign() math library function, but we are not able to rely on the existence of C99 functions here.
We provide this method on purpose only for the real-arithmetic specialization of GivensRotator. Complex numbers don't have a sign; they have an angle.
Definition at line 307 of file Teuchos_BLAS.hpp.