CompositeUnit#
- class astropy.units.CompositeUnit(scale, bases, powers, decompose=False, decompose_bases={}, _error_check=True)[source]#
Bases:
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:
- Raises:
UnitScaleError
If the scale is zero.
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:
- basespython: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.
- basespython:sequence of
- Returns:
- unit
CompositeUnit
New object containing only irreducible unit objects.
- unit