yt.units.yt_array.
YTQuantity
[source]¶A scalar associated with a unit.
Parameters: | input_scalar : an integer or floating point scalar
input_units : String unit specification, unit symbol object, or astropy units
registry : A UnitRegistry object
dtype : string or NumPy dtype object
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Examples
>>> from yt import YTQuantity
>>> a = YTQuantity(1, 'cm')
>>> b = YTQuantity(2, 'm')
>>> a + b
201.0 cm
>>> b + a
2.01 m
NumPy ufuncs will pass through units where appropriate.
>>> import numpy as np
>>> a = YTQuantity(12, 'g/cm**3')
>>> np.ones_like(a)
1 g/cm**3
and strip them when it would be annoying to deal with them.
>>> print(np.log10(a))
1.07918124605
YTQuantity is tightly integrated with yt datasets:
>>> import yt
>>> ds = yt.load('IsolatedGalaxy/galaxy0030/galaxy0030')
>>> a = ds.quan(5, 'code_length')
>>> a.in_cgs()
1.543e+25 cm
This is equivalent to:
>>> b = YTQuantity(5, 'code_length', registry=ds.unit_registry)
>>> np.all(a == b)
True
Methods