`separateUnits`

Splits a quantity into its numeric part and its units.

Category: Symbolic Computations in MATLAB > Units of Measurement

Syntax

[value, units] = separateUnits(expr)

Returns the part of expr without units and the units part.

Description

separateUnits is the inverse of attaching units by multiplication: value*units gives back the original quantity. With a single output only value is returned. An expression without units yields itself as value.

The pair is handy when a calculation must continue with plain doubles, using double(value), and the units are put back afterwards.

Input arguments

expr: Symbolic quantity, a product of a factor and units.

Output arguments

value: The numeric or symbolic factor.
units: The product of units, such as [km]/[s].

Example

Value and units of a speed

u = symunit;
[v, un] = separateUnits(3*u.km/u.s)
v*un

Output

v = 3
un = [km]/[s]
ans = 3*([km]/[s])

separateUnits