I

 

C

Language

Standard Library

Type support

Dynamic memory management

Error handling

Program utilities

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Input/output support

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Numerics

Common mathematical functions

Floating-point environment

Complex number arithmetics

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Type-generic math

 

Complex number arithmetic

Types and the imaginary constant
complex Complex_I CMPLX	imaginary Imaginary_I I
Manipulation
cimag creal carg	conj cproj
Power and exponential functions
cexp clog	cpow csqrt
Trigonometric functions
ccos csin ctan	cacos casin catan
Hyperbolic functions
ccosh csinh ctanh	cacosh casinh catanh

 

Defined in header <complex.h>
#define I /* unspecified */		(since C99)

The I macro expands to either Complex_I or Imaginary_I. If the implementation does not support imaginary types, then the macro always expands to Complex_I.

A program may undefine and perhaps then redefine the imaginary macro.

See also

Complex_I (C99)	the complex unit constant i (macro constant)
Imaginary_I (C99)	the imaginary unit constant i (macro constant)