CompositeUnit¶
-
class
astropy.units.
CompositeUnit
(scale, bases, powers, decompose=False, decompose_bases={}, _error_check=True)[source]¶ Bases:
astropy.units.UnitBase
Create a composite unit using expressions of previously defined units.
Direct use of this class is not recommended. Instead use the factory function
Unit
and arithmetic operators to compose units.- Parameters
scale : number
A scaling factor for the unit.
bases : sequence of
UnitBase
A sequence of units this unit is composed of.
powers : sequence of numbers
A sequence of powers (in parallel with
bases
) for each of the base units.
Attributes Summary
Return the bases of the composite unit.
Return the powers of the composite unit.
Return the scale of the composite unit.
Methods Summary
decompose
([bases])Return a unit object composed of only irreducible units.
is_unity
()Returns
True
if the unit is unscaled and dimensionless.Attributes Documentation
-
bases
¶ Return the bases of the composite unit.
-
powers
¶ Return the powers of the composite unit.
-
scale
¶ Return the scale of the composite unit.
Methods Documentation
-
decompose
(bases={})[source]¶ Return a unit object composed of only irreducible units.
- Parameters
bases : sequence of UnitBase, optional
The bases to decompose into. When not provided, decomposes down to any irreducible units. When provided, the decomposed result will only contain the given units. This will raises a
UnitsError
if it’s not possible to do so.- Returns
unit : CompositeUnit object
New object containing only irreducible unit objects.