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_format_name(format)

Get a name for this unit that is specific to a particular format.

is_equivalent(other[, equivalencies])

Returns True if this unit is equivalent to other.

is_unity()

Returns True if the unit is unscaled and dimensionless.

to_string([format])

Output the unit in the given format as a string.

Methods Documentation

get_format_name(format)[source]#

Get a name for this unit that is specific to a particular format.

Uses the dictionary passed into the format kwarg in the constructor.

Parameters:
formatstr

The name of the format

Returns:
namestr

The name of the unit for the given format.

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

Returns True if 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]#

Returns True if 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 instance or str

The name of a format or a formatter object. If not provided, defaults to the generic format.

**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).

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
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s