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std::complex should add missing C99 functionsSection: 28.4.7 [complex.value.ops] Status: CD1 Submitter: Daniel Krügler Opened: 2008-01-26 Last modified: 2016-01-28
Priority: Not Prioritized
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Discussion:
A comparision of the N2461 header <complex> synopsis ([complex.syn])
with the C99 standard (ISO 9899, 2nd edition and the two corrigenda) show
some complex functions that are missing in C++. These are:
cproj functions
cerf cerfc cexp2 cexpm1 clog10 clog1p clog2 clgamma ctgamma
I propose that at least the required cproj overloads are provided as equivalent
C++ functions. This addition is easy to do in one sentence (delegation to C99
function).
Please note also that the current entry polar
in 28.4.10 [cmplx.over] p. 1
should be removed from the mentioned overload list. It does not make sense to require that a
function already expecting scalar arguments
should cast these arguments into corresponding
complex<T> arguments, which are not accepted by
this function.
Proposed resolution:
In 28.4.2 [complex.syn] add just between the declaration of conj and fabs:
template<class T> complex<T> conj(const complex<T>&); template<class T> complex<T> proj(const complex<T>&); template<class T> complex<T> fabs(const complex<T>&);
In 28.4.7 [complex.value.ops] just after p.6 (return clause of conj) add:
template<class T> complex<T> proj(const complex<T>& x);Effects: Behaves the same as C99 function
cproj, defined in subclause 7.3.9.4."
In 28.4.10 [cmplx.over] p. 1, add one further entry proj to
the overload list.
The following function templates shall have additional overloads:
arg norm conjpolarproj imag real