NAME
units – conversion program

SYNOPSIS
units [ –v ] [ file ]

DESCRIPTION
Units converts quantities expressed in various standard scales to their equivalents in other scales. It works interactively in this fashion:
you have: inch
you want: cm
* 2.54
/ 0.393701

A quantity is specified as a multiplicative combination of units and floating point numbers. Operators have the following precedence:
+ –             add and subtract
* / x ÷           multiply and divide
catenation         multiply
² ³ ^            exponentiation
|               divide
( ... )            grouping

Most familiar units, abbreviations, and metric prefixes are recognized, together with a generous leavening of exotica and a few constants of nature including:
pi,π      ratio of circumference to diameter
c         speed of light
e         charge on an electron
g         acceleration of gravity
force     same as g
mole      
Avogadro's number
water     pressure head per unit height of water
au        astronomical unit

The pound is a unit of mass. Compound names are run together, e.g. lightyear. British units that differ from their US counterparts are prefixed thus: brgallon. Currency is denoted belgiumfranc, britainpound, etc.

Although units primatily does multiplicative scale changes, it can convert Centigrade to Fahrenheit and back.

The complete list of units can be found in /lib/units. A file argument to units specifies a file to be used instead of /lib/units. The –v flag causes units to print its entire database.

EXAMPLE
you have: 15 pounds force/in²
you want: atm
* 1.02069
/ .97973

FILES
/lib/units

SOURCE
/sys/src/cmd/units.y

BUGS
Currency conversions are only as accurate as the last time someone updated the database.
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