HP 15c - Manual (Page 65)

Section 3: Calculating in Complex Mode 65
then think of Z as
0.0000001234567890 × 10
−3
+ i(2.222222222 × 10
−3
).
then the accurate digits are
0.000000123 × 10
−3
+ i(2.222222222 × 10
−3
).
Applications
The capability of the HP-15C to work with complex numbers enables you to solve problems
that extend beyond the realm of real-valued numbers. On the following pages are several
programs that illustrate the usefulness of complex calculations—and the HP-15C.
Storing and Recalling Complex Numbers Using a Matrix
This program uses the stack and matrix C to store and recall complex numbers. It has the
following characteristics:

If you specify an index greater than the matrix's dimensions, the calculator displays
Error 3 and the stack is ready for another try.

If the calculator isn't in Complex mode, the program activates Complex mode and the
imaginary part of the number is set to zero.

When you store a complex number, the index is lost, the stack drops, and the
T-register is duplicated in the Z-register.

The "Store" program uses the Á key, which is above the O key. The "Recall"
program uses the E key, which is above the l key.
Keystrokes Display
|¥ Program mode.
´ CLEARM 000-
´bÁ 001-42,21,14 “Store” program.
´>1 002-42,16, 1 Sets R
0
= R
1
= 1.
O0 003- 44 0 R
0
= k.
) 004- 33
0 005- 0 Enters 0 in real (and imaginary)
X-registers.
+ 006- 40 Drops stack and has a + ib in
X-register.
´UOC
´U 007u 44 13 Stores a and increments indices
(User mode).
´} 008- 42 30
OC 009- 44 13 Stores b (no User mode here).
´} 010- 42 30 Restores a + ib in X-registers.