There are three supported notations for complex numbers in rectangular
form. The default is as a pair of real numbers enclosed in parentheses
and separated by a comma: `(a,b)'. The d c
(calc-complex-notation) command selects this style.
The other notations are d i (calc-i-notation), in which
numbers are displayed in `a+bi' form, and d j
(calc-j-notation) which displays the form `a+bj' preferred
in some disciplines.
Complex numbers are normally entered in `(a,b)' format.
If you enter `2+3i' as an algebraic formula, it will be stored as
the formula `2 + 3 * i'. However, if you use = to evaluate
this formula and you have not changed the variable `i', the `i'
will be interpreted as `(0,1)' and the formula will be simplified
to `(2,3)'. Other commands (like calc-sin) will not
interpret the formula `2 + 3 * i' as a complex number.
See section Variables, under "special constants."