HP -28S Quick Reference page 30

• The unit string may only contain a single divide sign "/". To the left
• Powers may only be in the range 1-9. In particular, they must not be
• Brackets for grouping are not allowed!
• Also, the unit may be preceeded by a magnitude prefix (see below)
• Single quotes inside the unit string are ignored.
Magnitude Symbol
prefixes E
P
T
G
M
k or K
h or H
D
Temperature These are special because additive constants are involved.
•
conversions
•
•
User defined
units
•
•
•
List of built-in units. The actual values can be retrieved from the calculator!
Unit Name
a Ar
A Ampere
acre Acre
arcmin Arcus Minute
100 "m*m" "ft^2" CONVERT results in 1076.39 "ft^2"
100 "m/s" "ft/s" CONVERT results in 328.08 "ft/s"
positive powers and to the right of it negative powers of units are
assumed.
negative.
100 "km/s" "mi/h" CONVERT results in 223693.63 "mi/h"
Warning: Some combinations of magnitude prefix and unit result in
another unit. Example: "min" is minutes but not milli-inches; "ft" is feet
but not femto-tons etc.
Name Factor 10E..
Exa 18
Peta 15
Tera 12
Giga 9
Mega 6
Kilo 3
Hecto 2
Deca 1
If there is only a plain temperature unit without magnitude prefix or
exponent or any other unit then absolute temperature conversion is
performed:
100 "°F" "°C" CONVERT results in 37.78 "°C"
Otherwise, a relative temperature conversion is performed which
ignores the additive constant:
50 "°F^2" "°C^2" CONVERT results in 30.86 "°C^2"
A user-defined unit is a length-2 list stored in a variable. The 1
element in the list is the factor to convert the unit into a built-in unit
and the 2 nd element is the built-in unit.
{7 "d"} 'wk' STO creates a unit wk (week) which consists of 7
days (d). It can be used like any other unit:
7 "wk" "h" CONVERT results in 168 "h"
Note that user-defined units cannot be preceeded by a magnitude
prefix. However, it is always possible to define a new user-unit that
has the prefix built into its name.
A dimension-less unit uses the unit string "1".
For non-SI units use the unit string "?". This can be used for example
to convert currency exchange rates.
HP-28S
Symbol
d
c
m
µ
n
p
F
a
Type
Area
Electric current
Area
Plane angle
30
Name Factor 10E..
Dezi -1
Centi -2
Milli -3
Micro -6
Nano -9
Pico -12
Femto -15
Atto -18
st
SI units
m^2
A
m^2
1