# DOUBLE COMPLEX

Statement: Specifies the DOUBLE COMPLEX data type.

DOUBLE COMPLEX

A COMPLEX(8) or DOUBLE COMPLEX constant is a pair of constants that represents a complex number. One of the pair must be a double-precision real constant, the other can be an integer, single-precision real, or double-precision real constant.

A COMPLEX(8) or DOUBLE COMPLEX constant occupies 16 bytes of memory and is interpreted as a complex number.

The rules for DOUBLE PRECISION (REAL(8)) constants also apply to the double precision portion of COMPLEX(KIND=8) or DOUBLE COMPLEX constants. (For more information, see REAL and DOUBLE PRECISION.)

The DOUBLE PRECISION constants in a COMPLEX(8) or DOUBLE COMPLEX constant have IEEE* binary64 format.

## Example

    DOUBLE COMPLEX vector, arrays(7,29)
    DOUBLE COMPLEX pi, pi2 /3.141592654,6.283185308/

Valid COMPLEX(8) or DOUBLE COMPLEX constants
(547.3E0_8,-1.44_8)
(1.7039E0,-1.7039D0)
(+12739D3,0.D0)

Invalid COMPLEX(8) or DOUBLE COMPLEX constants
(1.23D0,) | Second constant missing.
(1D1,2H12) | Hollerith constants not allowed.
(1,1.2) | Neither constant is DOUBLE PRECISION; this is a valid single-precision real constant.

Parent topic: C to D

## See Also

General Rules for Complex Constants
COMPLEX Statement
Complex Data Types
DOUBLE PRECISION
REAL