uexpr

uexpr
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uexpr

uexpr is a Tcl package for calculating with units.

See the manual page.

Download the latest version.

uexpr requires a fairly recent Tcl8.6

Some examples:

package require uexpr

uexpr 3ft + 8.56cm = m

returns 1.0 m (well actually 1.00...02 m)

Using package require uexpr=

loads the package and aliases uexpr to "=" so:

= 3in * 7in * 11in = in^3

returns 231.0 in^3

or

= 3in*7in*11in=gal

returns 1.0 gal

Acres in a square mile:

= 1mile^2=acre

returns 640.0 acre

Area of a circle with a given diameter:

set d 1in

= pi/4*d^2=in^2

returns 0.785398... in^2

pi is a built in constant, d is a Tcl variable

uexpr::unitNames returns a list of all units and constants currently available.

increase in temperature of water falling 1000 ft in an insulated pipe, given heat capacity of water and height it falls:

set Cpw "1 cal/gram degC"

set h 1000ft

= g*h/Cpw=degF

should return 1.285... degF. See notes on man page about absolute, biased and differential units (degF/degR degC/degK, absolute, gauge and differenial pressures).

uexpr requires a fairly recent version of Tcl8.6

See the manual page.

Download the latest version.