Defined in header <cmath> float tan( float arg ); (1) double tan( double arg ); (2) long double tan( long double arg ); (3) double tan( Integral arg ); (4) (since C++11) Computes the tangent of arg (measured in radians). 4) A set of overloads or a function template accepting an argument of any integral type. Equivalent to 2) (the argument is cast to double). Parameters arg - value representing angle in radians, of a floating-point

virtual const char* what() const; (since C++11) Returns the explanatory string. Parameters (none). Return value Pointer to a null-terminated string with explanatory information. Exceptions noexcept specification: noexcept See also code returns error code (public member function)

system_error( std::error_code ec ); (1) (since C++11) system_error( std::error_code ec, const std::string& what_arg ); (2) (since C++11) system_error( std::error_code ec, const char* what_arg ); (2) (since C++11) system_error( int ev, const std::error_category& ecat ); (3) (since C++11) system_error( int ev, const std::error_category& ecat, const std::string& what_arg); (4) (since C++11) system_error( int ev, const std::error_category

const std::error_code& code() const; (since C++11) Returns the stored error code. Parameters (none). Return value The stored error code. Exceptions noexcept specification: noexcept See also what [virtual] returns explanatory string (virtual public member function)

Defined in header <system_error> class system_error; (since C++11) std::system_error is the type of the exception thrown by various library functions (typically the functions that interface with the OS facilities, e.g. the constructor of std::thread) when the exception has an associated std::error_code, which may be reported. Inheritance diagram. Member functions (constructor) constructs the system_error object (public member function) code returns error c

Defined in header <system_error> const std::error_category& system_category(); (since C++11) Obtains a reference to the static error category object for errors reported by the operating system. The object is required to override the virtual function std::error_category::name() to return a pointer to the string "system". It is also required to override the virtual function std::error_category::default_error_condition() to map the error codes that match POSIX errno values

Defined in header <cstdlib> int system( const char* command ); Calls the host environment's command processor (/bin/sh, cmd.exe, command.com) with the parameter command. Returns an implementation-defined value (usually the value that the invoked program returns). If command is a null pointer, checks if host environment has a command processor and returns nonzero value only if the command processor exists. Parameters command - character string identifying the command

Defined in header <algorithm> template< class ForwardIt1, class ForwardIt2 > ForwardIt2 swap_ranges( ForwardIt1 first1, ForwardIt1 last1, ForwardIt2 first2 ); Exchanges elements between range [first1, last1) and another range starting at first2. Parameters first1, last1 - the first range of elements to swap first2 - beginning of the second range of elements to swap Type requirements - ForwardIt1, ForwardIt2 must meet the requirements of ForwardIterat

template< class T > void swap( weak_ptr<T>& lhs, weak_ptr<T>& rhs ); (since C++11) Specializes the std::swap algorithm for std::weak_ptr. Swaps the pointers of lhs and rhs. Calls lhs.swap(rhs). Parameters lhs, rhs - smart pointers whose contents to swap Return value (none). Exceptions noexcept specification: noexcept Complexity Constant. See also swap swaps the values of two objects (function template) swap swaps the contents (

template< class T, class Alloc > void swap( vector<T,Alloc>& lhs, vector<T,Alloc>& rhs ); Specializes the std::swap algorithm for std::vector. Swaps the contents of lhs and rhs. Calls lhs.swap(rhs). Parameters lhs, rhs - containers whose contents to swap Return value (none). Complexity Constant. Exceptions noexcept specification: noexcept(noexcept(lhs.swap(rhs))) (since C++17) See also swap swaps the contents (public