HP HP-21 - HP-21 Functions and Keyboard Index

HP-21 Functions and Keyboard Index
of Mo~ Power
switch (page 8).
oee MR Selects
degrees or radians
for trigonometric
functions (page 44).
Computes
reciprocal of number
in display (page 39).
Raises number
in Y-register to power
of number in display
(page 50).
SIN Gives
sine, cosine, or
tangent of numberin
display (page 43).
Gives
arc sine, arc cosine,
or arc tangent of
number in display
(page 43).
- Press before
function key to select
function printed in
blue on slanted key
face (page 9).
Interchange.
Exchanges contents
of displayed X-
register with the
contents of the Y-
register (page 37).
Rectangular
coordinate con-
version. Converts
polar magnitude and
angle in X and Y
registers to
rectangular x and y
coordinates
(page 46).
X Rolls down
contents of stack
forviewingindisplay
(page 26).
Polar coordinate
conversion. Con-
verts x, y rectangular
coordinates placed
in X and Y registers
to polar magnitude
and angle (page 46).
m Natural antilog.
Raises e (2.718 . . .)
to power of value in
display (page 48).
Natu ral logarithm.
Computes natural
logarithm (base e,
2.718 .. .)ofvaluein
display (page 48).
Storesdisplayed
number in manual
storage register
(page 41).
Common
logarithm. Computes
common logarithm
(base 10) of displayed
number (page 49).
Recall. Copies
stored number from
manual storage
register into display
(page 41).
E Common anti-
logarithm. Raises 10
to the power of the
number in the dis-
play (page 49).
Copies
number in displayed
X-register into Y-
register (page 10).
Changes sign of
displayed number
and/or exponent of
ten (page 8).
Computes
square root of
displayed number
(page 39).
@Enter exponent.
Tells display that the
next numbers keyed
in are powers of 10
(page 21).
Displays value of
pi (3.14..))
(page 40).
Clear x.
Replaces number in
displayed X-register
with 0 (page 8).
Clear. Replaces
all numbers in the
automatic memory
stack (including the
displayed X-register)
with 0’s (page 29).
(=) [x] [+]
Arithmetic
operations (page 10).
Storage arithmetic.
Operation performed
upon number in
manual storage
register by number
in display (page 42).
Display. Selects
fixed decimal point
or scientific display
notation (page 17).