Complex
Complex is the head used for complex numbers.
You can enter a complex number in the form x + I y.
_Complex can be used to stand for a complex number in a pattern.
You have to use Re and Im to extract parts of Complex numbers.
See The Mathematica Book on the web: Section 3.1.1.
See also: Complexes, Real, Re, Im.
Further Examples
This number xx is only approximately real.
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Chop gets rid of the small imaginary part.
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This defines the rule rr that converts a complex number into a list made up of its real and imaginary parts.
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You can apply the rule to all the elements of a list.
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