UnrecognizedUnit#

class astropy.units.UnrecognizedUnit(st, doc=None, format=None, namespace=None)[source]#

Bases: IrreducibleUnit

A unit that did not parse correctly. This allows for round-tripping it as a string, but no unit operations actually work on it.

Parameters:

ststr: The name of the unit.

Methods Summary

`get_converter`(other[, equivalencies])	Create a function that converts values from this unit to another.
`is_equivalent`(other[, equivalencies])	Check whether this unit is equivalent to `other`.
`is_unity`()	Check whether the unit is unscaled and dimensionless.
`to_string`([format])	Output the unit in the given format as a string.

Methods Documentation

get_converter(other, equivalencies=None)[source]#

Create a function that converts values from this unit to another.

Parameters:

otherastropy:unit-like: The unit to convert to.
equivalencieslist of tuple: A list of equivalence pairs to try if the units are not directly convertible. See Equivalencies. This list is in addition to possible global defaults set by, e.g., set_enabled_equivalencies. Use None to turn off all equivalencies.

Returns:

funccallable(): A callable that takes an array-like argument and returns it converted from units of self to units of other.

Raises:

UnitsError: If the units cannot be converted to each other.

Notes

This method is used internally in Quantity to convert to different units. Note that the function returned takes and returns values, not quantities.

is_equivalent(other, equivalencies=None)[source]#

Check whether this unit is equivalent to other.

Parameters:

otherUnit, str, or tuple: The unit to convert to. If a tuple of units is specified, this method returns true if the unit matches any of those in the tuple.
equivalencieslist of tuple: A list of equivalence pairs to try if the units are not directly convertible. See Equivalencies. This list is in addition to possible global defaults set by, e.g., set_enabled_equivalencies. Use None to turn off all equivalencies.

Returns:

bool

is_unity()[source]#: Check whether the unit is unscaled and dimensionless.

to_string(format=None)[source]#

Output the unit in the given format as a string.

Parameters:

formatastropy.units.format.Base subclass or str or None

The name of a format or a formatter class. If not provided (or None), defaults to the generic format.

deprecations{“warn”, “silent”, “raise”, “convert”}, optional, keyword-only

Whether deprecated units should emit a warning, be handled silently or raise an error. The “convert” option replaces the deprecated unit if possible and emits a warning otherwise.

**kwargs

Further options forwarded to the formatter. Currently recognized is fraction, which can take the following values:

False : display unit bases with negative powers as they are;
‘inline’ or True : use a single-line fraction;
‘multiline’ : use a multiline fraction (available for the ‘latex’, ‘console’ and ‘unicode’ formats only; for others, an ‘inline’ fraction is used).

Raises:

TypeError: If format is of the wrong type.
ValueError: If format or fraction are not recognized.

Examples

>>> import astropy.units as u
>>> kms = u.Unit('km / s')
>>> kms.to_string()  # Generic uses fraction='inline' by default
'km / s'
>>> kms.to_string('latex')  # Latex uses fraction='multiline' by default
'$\\mathrm{\\frac{km}{s}}$'
>>> print(kms.to_string('unicode', fraction=False))
km s⁻¹
>>> print(kms.to_string('unicode', fraction='inline'))
km / s
>>> print(kms.to_string('unicode', fraction='multiline'))
km
──
s