# Applications; Storing And Recalling Complex Numbers Using A Matrix - HP -15C Advanced Functions Handbook

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SectionS: Calculating in Complex Mode
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 [5] key, which is above the | STO |
key. The "Recall" program uses the |T| key, which is above the
iRCLlkey.
Keystrokes
[jDQVR]
Q] CLEAR [PRGM]
Display
000-
001-42,21,14
002-42,16, 1
003-
44 0
004-
33
005-
0
006-
40
007u
4 4 1 3
008-
42 30
Program mode.
"Store" program.
Enters 0 in real (and
imaginary) X-registers.
Drops stack and has
a + ib in X-register.
Stores a and increments
indices (User mode).