units - Maple Help

convert/units

convert between units

 Calling Sequence convert(expr, 'units', unitFrom, unitTo, opts) convert(exprWithUnit), 'units', unitTo, opts)

Parameters

 expr - expression unitFrom - symbol; unit to be converted from unitTo - symbol; unit to be converted to exprWithUnit - expression with unit opts - (optional) equation(s) of the form option=value where option is one of energy or symbolic; specify options for the conversion

Description

 • The convert(expr, 'units', unitFrom, unitTo) command multiplies the value u by the conversion factor from unitFrom to unitTo.
 • The units unitTo and unitFrom can be labeled in any way accepted by the Units package, for example, name, abbreviation, or symbol.
 • For the second calling sequence, exprWithUnit can be any expression with a unit attached in any valid way.  This can be, for example, 3*Unit('cm') or an expression with a unit added from the Units palette.
 Notes:
 – To enter a unit in 2-D Math input, select the unit from the appropriate Units palette. If the unit you want is not there, select $\mathrm{unit}$ and then enter the unit.
 – When you edit a unit, double brackets appear around it.
 Note: Thermodynamic temperature conversions are for temperature intervals, not absolute temperatures. For example, 1 degree Celsius is converted to 1 kelvin, not 274.15 kelvin.  For conversions of absolute temperatures, use convert/temperature.
 • You can modify the properties of the conversion by including options opts. The opts argument can contain one or more of the following equations.
 'energy'=true or false
 If this option is set to true, the conversion can be between energy units, not necessarily units with the same dimensions. Furthermore, unitTo can be set to $1$ to convert to a dimensionless quantity.  For more information about energy transformations, see Energy Conversions.
 'symbolic'=true or false
 This option specifies whether annotations to units should be ignored.  By default, this option is set to false.

Examples

 > $\mathrm{convert}\left(100.0,'\mathrm{units}','\mathrm{ft}','m'\right)$
 ${30.48000000}$ (1)
 > $\mathrm{convert}\left(46145,'\mathrm{units}','\mathrm{yards}','\mathrm{kilometers}'\right)$
 $\frac{{10548747}}{{250000}}$ (2)
 > $\mathrm{convert}\left(120,'\mathrm{units}','W','\mathrm{hp}'\right)$
 $\frac{{2000000000000000}}{{12428331193037837}}$ (3)
 > $\mathrm{convert}\left(1,'\mathrm{units}','\mathrm{permittivity}\left[\mathrm{Atomic}\right]',1,'\mathrm{energy}'=\mathrm{true}\right)$
 ${1}$ (4)

In the next two examples, the expression being converted has a unit associated with it. Here, only the unitTo parameter needs to provided.

 > $\mathrm{convert}\left(5\mathrm{Unit}\left(Nm\left(\mathrm{radius}\right)\right),'\mathrm{units}',Nm,'\mathrm{symbolic}'=\mathrm{true}\right)$
 ${5}{}⟦{N}{}{m}⟧$ (5)
 > $\mathrm{with}\left(\mathrm{Units}\left[\mathrm{Standard}\right]\right):$
 > $3\mathrm{Unit}\left(\frac{'\mathrm{kg}''m'}{'s'}\right)$
 ${3}{}⟦\frac{{\mathrm{kg}}{}{m}}{{s}}⟧$ (6)
 > $\mathrm{convert}\left(,'\mathrm{units}',\frac{'\mathrm{lb}''\mathrm{ft}'}{'h'}\right)$
 $\frac{{450000000000000}}{{5760623099}}{}⟦\frac{{\mathrm{lb}}{}{\mathrm{ft}}}{{h}}⟧$ (7)