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 Variables, under “special constants.”