CylindricalRepresentation¶

class
astropy.coordinates.
CylindricalRepresentation
(rho, phi, z, differentials=None, copy=True)[source]¶ Bases:
astropy.coordinates.BaseRepresentation
Representation of points in 3D cylindrical coordinates.
Parameters:  rho :
Quantity
The distance from the z axis to the point(s).
 phi :
Quantity
or str 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. copy : bool, optional
If
True
(default), arrays will be copied rather than referenced.
Attributes Summary
attr_classes
phi
The azimuth of the point(s). rho
The distance of the point(s) from the zaxis. z
The height of the point(s). Methods Summary
from_cartesian
(cart)Converts 3D rectangular cartesian coordinates to cylindrical polar coordinates. scale_factors
()Scale factors for each component’s direction. to_cartesian
()Converts cylindrical polar coordinates to 3D rectangular cartesian coordinates. unit_vectors
()Cartesian unit vectors in the direction of each component. Attributes Documentation

attr_classes
= {'phi': <class 'astropy.coordinates.angles.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 zaxis.

z
¶ The height of the point(s).
Methods Documentation

classmethod
from_cartesian
(cart)[source]¶ Converts 3D rectangular cartesian coordinates to cylindrical polar coordinates.

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 \(\delta c \times f_c \times \hat{e}_c\).
Returns:  scale_factors : dict of
Quantity
The keys are the component names.
 scale_factors : dict of

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 of
CartesianRepresentation
The keys are the component names.
 unit_vectors : dict of
 rho :