PPVStatistic¶
- class astrodendro.analysis.PPVStatistic(stat, metadata=None)¶
Bases:
SpatialBase
Compute properties of structures in a position-position-velocity (PPV) cube.
- Parameters:
- structure
Structure
instance The structure to compute the statistics for
- metadatadict
Key-value pairs of metadata
- structure
Attributes Summary
The exact area of the structure on the sky.
The integrated flux of the structure, in Jy (note that this does not include any kind of background subtraction, and is just a plain sum of the values in the structure, converted to Jy).
The position angle of sky_maj, sky_min in degrees counter-clockwise from the +x axis (note that this is the +x axis in pixel coordinates, which is the
-x
axis for conventional astronomy images).The mean velocity of the structure (where the velocity axis can be specified by the
vaxis
metadata parameter, which defaults to 0 following the Numpy convention - the third axis in the FITS convention).Intensity-weighted second moment of velocity (where the velocity axis can be specified by the
vaxis
metadata parameter, which defaults to 0 following the Numpy convention - the third axis in the FITS convention).A descriptor to wrap around metadata dictionaries.
The mean position of the structure in the x direction.
The mean position of the structure in the y direction.
Attributes Documentation
- area_exact¶
The exact area of the structure on the sky.
- flux¶
The integrated flux of the structure, in Jy (note that this does not include any kind of background subtraction, and is just a plain sum of the values in the structure, converted to Jy).
- position_angle¶
The position angle of sky_maj, sky_min in degrees counter-clockwise from the +x axis (note that this is the +x axis in pixel coordinates, which is the
-x
axis for conventional astronomy images).
- v_cen¶
The mean velocity of the structure (where the velocity axis can be specified by the
vaxis
metadata parameter, which defaults to 0 following the Numpy convention - the third axis in the FITS convention).
- v_rms¶
Intensity-weighted second moment of velocity (where the velocity axis can be specified by the
vaxis
metadata parameter, which defaults to 0 following the Numpy convention - the third axis in the FITS convention).
- vaxis¶
A descriptor to wrap around metadata dictionaries.
Lets classes reference self.x instead of self.metadata[‘x’],
- velocity_scale¶
- x_cen¶
The mean position of the structure in the x direction.
- y_cen¶
The mean position of the structure in the y direction.