CylindricalRepresentation#
- class astropy.coordinates.CylindricalRepresentation(rho, phi=None, z=None, differentials=None, copy=True)[source]#
Bases:
BaseRepresentation
Representation of points in 3D cylindrical coordinates.
- Parameters:
- rho
Quantity
The distance from the z axis to the point(s).
- phi
Quantity
orstr
The azimuth of the point(s), in angular units, which will be wrapped to an angle between 0 and 360 degrees. This can also be instances of
Angle
,- z
Quantity
The z coordinate(s) of the point(s)
- differentials
dict
,CylindricalDifferential
, optional Any differential classes that should be associated with this representation. The input must either be a single
CylindricalDifferential
instance, or a dictionary of of differential instances with keys set to a string representation of the SI unit with which the differential (derivative) is taken. For example, for a velocity differential on a positional representation, the key would be's'
for seconds, indicating that the derivative is a time derivative.- copybool, optional
If
True
(default), arrays will be copied. IfFalse
, arrays will be references, though possibly broadcast to ensure matching shapes.
- rho
Attributes Summary
The azimuth of the point(s).
The distance of the point(s) from the z-axis.
The height of the point(s).
Methods Summary
from_cartesian
(cart)Converts 3D rectangular cartesian coordinates to cylindrical polar coordinates.
represent_as
(other_class[, differential_class])Convert coordinates to another representation.
Scale factors for each component's direction.
Converts cylindrical polar coordinates to 3D rectangular cartesian coordinates.
Cartesian unit vectors in the direction of each component.
Attributes Documentation
- attr_classes = {'phi': <class 'astropy.coordinates.angles.core.Angle'>, 'rho': <class 'astropy.units.quantity.Quantity'>, 'z': <class 'astropy.units.quantity.Quantity'>}#
- phi#
The azimuth of the point(s).
- rho#
The distance of the point(s) from the z-axis.
- z#
The height of the point(s).
Methods Documentation
- classmethod from_cartesian(cart)[source]#
Converts 3D rectangular cartesian coordinates to cylindrical polar coordinates.
- represent_as(other_class, differential_class=None)[source]#
Convert coordinates to another representation.
If the instance is of the requested class, it is returned unmodified. By default, conversion is done via Cartesian coordinates. Also note that orientation information at the origin is not preserved by conversions through Cartesian coordinates. See the docstring for
to_cartesian()
for an example.- Parameters:
- other_class
BaseRepresentation
subclass The type of representation to turn the coordinates into.
- differential_class
dict
ofBaseDifferential
, optional Classes in which the differentials should be represented. Can be a single class if only a single differential is attached, otherwise it should be a
dict
keyed by the same keys as the differentials.
- other_class
- scale_factors()[source]#
Scale factors for each component’s direction.
Given unit vectors \(\hat{e}_c\) and scale factors \(f_c\), a change in one component of \(\delta c\) corresponds to a change in representation of \(\delta c \times f_c \times \hat{e}_c\).
- to_cartesian()[source]#
Converts cylindrical polar coordinates to 3D rectangular cartesian coordinates.
- unit_vectors()[source]#
Cartesian unit vectors in the direction of each component.
Given unit vectors \(\hat{e}_c\) and scale factors \(f_c\), a change in one component of \(\delta c\) corresponds to a change in representation of \(\delta c \times f_c \times \hat{e}_c\).
- Returns:
- unit_vectors
dict
ofCartesianRepresentation
The keys are the component names.
- unit_vectors