Definition: The sum of a real number and an imaginary number is called a complex number. Babel supports complex numbers as a basic type via the basic types ``fcomplex'' and ``dcomplex.''
SIDL keyword: dcomplex is a data type built into SIDL. The name is short for ``double complex.'' It stores a complex number via 2 64-bit floating point variables, one for the real part, and one for the imaginary part.