Tham khảo tài liệu 'the new c standard- p6', công nghệ thông tin, kỹ thuật lập trình phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Types 503 1 ifdef _cplusplus 2 3 include complex 4 5 typedef complex float float_complex 6 typedef complex double double_complex 7 typedef complex long double long_double_complex 8 9 else 10 11 include 12 13 typedef float complex float_complex 14 typedef double complex double_complex 15 typedef long double complex long_double_complex 16 endif Other Languages Fortran has contained complex types since an early version of that standard. Few other languages specify a built-in complex type . Ada Common Lisp and Scheme . Common Implementations Very few processors support instructions that operate on complex types. Implementations invariably break down the operations into their constituent real and imaginary parts and operate on those separately. gcc supports integer complex types. Any of the integer type specifiers may be used. Coding Guidelines The use of built-in language types may offer some advantages over developer-defined representations optimizers have more information available to them and may be able to generate more efficient code . However the cost involved in changing existing code to use this type is likely to be larger than the benefits reaped. 501 The real floating and complex types are collectively called the floating types. floating types Commentary This defines the term floating types. C90 What the C90 Standard calls floating types includes complex types in C99. Coding Guidelines There is plenty of opportunity for confusion over this terminology. Common developer usage did not use to distinguish between complex and real types it did not need to. Developers who occasionally make use of floating-point types will probably be unaware of the distinction made by the C Standard between real and complex. The extent to which correct terminology will be used within the community that uses complex types is unknown. 502 For each floating type there is a corresponding real type which is always a real floating type. Commentary This defines the .