Difference between revisions of "cpp/numeric/complex/operator""i"
From cppreference.com
(note that if isn't a keyword here) |
m (correct if note a bit) |
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These operators are declared in the namespace {{c|std::literals::complex_literals}}, where both {{tt|literals}} and {{tt|complex_literals}} are inline namespaces. Access to these operators can be gained with {{c|using namespace std::literals}} and {{c|using namespace std::literals::complex_literals}}. | These operators are declared in the namespace {{c|std::literals::complex_literals}}, where both {{tt|literals}} and {{tt|complex_literals}} are inline namespaces. Access to these operators can be gained with {{c|using namespace std::literals}} and {{c|using namespace std::literals::complex_literals}}. | ||
| − | Even though {{c|if}} is a [[cpp/keywords/if|keyword]] in C++, it is | + | Even though {{c|if}} is a [[cpp/keywords/if|keyword]] in C++, it is a {{spar|ud-suffix}} of the [[cpp/language/user_literal|literal operator]] of the form {{c|operator ""if}} and in the literal expressions such as {{c|1if}} or {{c|1.0if}} because it is not separated by whitespace and is not a standalone token. |
===Example=== | ===Example=== | ||
Revision as of 10:48, 6 June 2014
| Defined in header <complex>
|
||
| constexpr complex<long double> operator""il(long double arg); constexpr complex<long double> operator""il(unsigned long long arg); |
(1) | (since C++14) |
| constexpr complex<double> operator""i(long double arg); constexpr complex<double> operator""i(unsigned long long arg); |
(2) | (since C++14) |
| constexpr complex<float> operator""if(long double arg); constexpr complex<float> operator""if(unsigned long long arg); |
(3) | (since C++14) |
Forms a std::complex literal representing an imaginary number.
Contents |
Parameters
| arg | - | the value of the imaginary number |
Return value
The std::complex literal with the real part zero and imaginary part arg
Possible implementation
constexpr std::complex<double> operator""i(unsigned long long d); { return std::complex<double>{0.0, static_cast<double>(d)}. } constexpr std::complex<long double> operator""i(double d); { return std::complex<double>{0.0, d}. } |
Notes
These operators are declared in the namespace std::literals::complex_literals, where both literals and complex_literals are inline namespaces. Access to these operators can be gained with using namespace std::literals and using namespace std::literals::complex_literals.
Even though if is a keyword in C++, it is a ud-suffix of the literal operator of the form operator ""if and in the literal expressions such as 1if or 1.0if because it is not separated by whitespace and is not a standalone token.
Example
Run this code
#include <iostream> #include <complex> int main() { using namespace std::literals::complex_literals; std::complex<double> c = 1.0 + 1i; std::cout << "abs" << c << " = " << abs(c) << '\n'; }
Output:
abs(1,1) = 1.41421
See also
| constructs a complex number (public member function) |
