IsophoteList¶

class
photutils.isophote.
IsophoteList
(iso_list)[source]¶ Bases:
object
Container class that provides the same attributes as the
Isophote
class, but for a list of isophotes.The attributes of this class are arrays representing the values of the attributes for the entire list of
Isophote
instances. See theIsophote
class for a description of the attributes.The class extends the
list
functionality, thus provides basic list behavior such as slicing, appending, and support for ‘+’ and ‘+=’ operators.Attributes Summary
A thirdorder harmonic coefficent.
The error associated with
a3
.A fourthorder harmonic coefficent.
The error associated with
a4
.A thirdorder harmonic coefficent.
The error associated with
b3
.A fourthorder harmonic coefficent.
The error associated with
b3
.The ellipticity error.
The ellipticity of the ellipse.
The local radial intensity gradient.
The measurement error of the local radial intensity gradient.
The relative error of local radial intensity gradient.
The error of the mean intensity (rms / sqrt(# data points)).
The mean intensity value along the elliptical path.
The number of extracted data points.
The number of discarded data points.
The number of iterations used to fit the isophote.
The total number of valid pixels inside a circle with the same
sma
as the ellipse.The total number of valid pixels inside the ellipse.
The position angle (radians) of the ellipse.
The position angle error (radians).
The estimate of pixel standard deviation (rms * sqrt(average sector integration area)).
The rootmeansquare of intensity values along the elliptical path.
The isophote
EllipseSample
information.The average sector area on the isophote (pixel**2).
The semimajor axis length (pixels).
The fitting stop code.
The sum of all pixels inside a circle with the same
sma
as the ellipse.The sum of all pixels inside the ellipse.
The status of the fitting operation.
The center x coordinate (pixel).
The error associated with the center x coordinate.
The center y coordinate (pixel).
The error associated with the center y coordinate.
Methods Summary
append
(value)extend
(value)get_closest
(sma)Return the
Isophote
instance that has the closest semimajor axis length to the input semimajor axis.insert
(index, value)sort
()to_table
()Convert an
IsophoteList
instance to aQTable
with the main isophote parameters.Attributes Documentation

a3
¶ A thirdorder harmonic coefficent. See the
fit_upper_harmonic()
function for details.

a4
¶ A fourthorder harmonic coefficent. See the
fit_upper_harmonic()
function for details.

b3
¶ A thirdorder harmonic coefficent. See the
fit_upper_harmonic()
function for details.

b4
¶ A fourthorder harmonic coefficent. See the
fit_upper_harmonic()
function for details.

ellip_err
¶ The ellipticity error.

eps
¶ The ellipticity of the ellipse.

grad
¶ The local radial intensity gradient.

grad_error
¶ The measurement error of the local radial intensity gradient.

grad_r_error
¶ The relative error of local radial intensity gradient.

int_err
¶ The error of the mean intensity (rms / sqrt(# data points)).

intens
¶ The mean intensity value along the elliptical path.

ndata
¶ The number of extracted data points.

nflag
¶ The number of discarded data points. Data points can be discarded either because they are physically outside the image frame boundaries, because they were rejected by sigmaclipping, or they are masked.

niter
¶ The number of iterations used to fit the isophote.

npix_c
¶ The total number of valid pixels inside a circle with the same
sma
as the ellipse.

npix_e
¶ The total number of valid pixels inside the ellipse.

pa
¶ The position angle (radians) of the ellipse.

pa_err
¶ The position angle error (radians).

pix_stddev
¶ The estimate of pixel standard deviation (rms * sqrt(average sector integration area)).

rms
¶ The rootmeansquare of intensity values along the elliptical path.

sample
¶ The isophote
EllipseSample
information.

sarea
¶ The average sector area on the isophote (pixel**2).

sma
¶ The semimajor axis length (pixels).

stop_code
¶ The fitting stop code.

tflux_c
¶ The sum of all pixels inside a circle with the same
sma
as the ellipse.

tflux_e
¶ The sum of all pixels inside the ellipse.

valid
¶ The status of the fitting operation.

x0
¶ The center x coordinate (pixel).

x0_err
¶ The error associated with the center x coordinate.

y0
¶ The center y coordinate (pixel).

y0_err
¶ The error associated with the center y coordinate.
Methods Documentation

get_closest
(sma)[source]¶ Return the
Isophote
instance that has the closest semimajor axis length to the input semimajor axis. Parameters
 smafloat
The semimajor axis length.
 Returns
 isophote
Isophote
instance The isophote with the closest semimajor axis value.
 isophote

to_table
()[source]¶ Convert an
IsophoteList
instance to aQTable
with the main isophote parameters. Returns
 result
QTable
An astropy QTable with the main isophote parameters.
 result
