"""The ``region_translators`` module houses translations of
:ref:`regions:shapes` to :ref:`photutils:photutils-aperture` apertures.
"""
from astropy import units as u
from astropy.coordinates import Angle
from photutils.aperture import (CircularAperture, SkyCircularAperture,
EllipticalAperture, SkyEllipticalAperture,
RectangularAperture, SkyRectangularAperture,
CircularAnnulus, SkyCircularAnnulus,
EllipticalAnnulus, SkyEllipticalAnnulus,
RectangularAnnulus, SkyRectangularAnnulus)
from regions import (CirclePixelRegion, CircleSkyRegion,
EllipsePixelRegion, EllipseSkyRegion,
RectanglePixelRegion, RectangleSkyRegion,
CircleAnnulusPixelRegion, CircleAnnulusSkyRegion,
EllipseAnnulusPixelRegion, EllipseAnnulusSkyRegion,
RectangleAnnulusPixelRegion, RectangleAnnulusSkyRegion, PixCoord)
__all__ = ['regions2aperture', 'aperture2regions']
[docs]def regions2aperture(region_shape):
"""Convert a given ``regions`` shape to ``photutils`` aperture.
Parameters
----------
region_shape : `regions.Region`
A supported ``regions`` shape.
Returns
-------
aperture : `photutils.aperture.Aperture`
An equivalent ``photutils`` aperture.
Raises
------
NotImplementedError
The given ``regions`` shape is not supported.
Examples
--------
Translate a `regions.CirclePixelRegion` to `photutils.aperture.CircularAperture`:
>>> from regions import CirclePixelRegion, PixCoord
>>> from jdaviz.core.region_translators import regions2aperture
>>> region_shape = CirclePixelRegion(center=PixCoord(x=42, y=43), radius=4.2)
>>> regions2aperture(region_shape)
<CircularAperture([42., 43.], r=4.2)>
Also see
--------
aperture2regions
"""
if isinstance(region_shape, CirclePixelRegion):
aperture = CircularAperture(region_shape.center.xy, region_shape.radius)
elif isinstance(region_shape, CircleSkyRegion):
aperture = SkyCircularAperture(region_shape.center, region_shape.radius)
elif isinstance(region_shape, EllipsePixelRegion):
aperture = EllipticalAperture(
region_shape.center.xy, region_shape.width * 0.5, region_shape.height * 0.5,
theta=region_shape.angle.to_value(u.radian))
elif isinstance(region_shape, EllipseSkyRegion):
aperture = SkyEllipticalAperture(
region_shape.center, region_shape.width * 0.5, region_shape.height * 0.5,
theta=region_shape.angle)
elif isinstance(region_shape, RectanglePixelRegion):
aperture = RectangularAperture(
region_shape.center.xy, region_shape.width, region_shape.height,
theta=region_shape.angle.to_value(u.radian))
elif isinstance(region_shape, RectangleSkyRegion):
aperture = SkyRectangularAperture(
region_shape.center, region_shape.width, region_shape.height, theta=region_shape.angle)
elif isinstance(region_shape, CircleAnnulusPixelRegion):
aperture = CircularAnnulus(
region_shape.center.xy, region_shape.inner_radius, region_shape.outer_radius)
elif isinstance(region_shape, CircleAnnulusSkyRegion):
aperture = SkyCircularAnnulus(
region_shape.center, region_shape.inner_radius, region_shape.outer_radius)
elif isinstance(region_shape, EllipseAnnulusPixelRegion):
aperture = EllipticalAnnulus(
region_shape.center.xy, region_shape.inner_width * 0.5, region_shape.outer_width * 0.5,
region_shape.outer_height * 0.5, b_in=region_shape.inner_height * 0.5,
theta=region_shape.angle.to_value(u.radian))
elif isinstance(region_shape, EllipseAnnulusSkyRegion):
aperture = SkyEllipticalAnnulus(
region_shape.center, region_shape.inner_width * 0.5, region_shape.outer_width * 0.5,
region_shape.outer_height * 0.5, b_in=region_shape.inner_height * 0.5,
theta=region_shape.angle)
elif isinstance(region_shape, RectangleAnnulusPixelRegion):
aperture = RectangularAnnulus(
region_shape.center.xy, region_shape.inner_width, region_shape.outer_width,
region_shape.outer_height, h_in=region_shape.inner_height,
theta=region_shape.angle.to_value(u.radian))
elif isinstance(region_shape, RectangleAnnulusSkyRegion):
aperture = SkyRectangularAnnulus(
region_shape.center, region_shape.inner_width, region_shape.outer_width,
region_shape.outer_height, h_in=region_shape.inner_height, theta=region_shape.angle)
else:
raise NotImplementedError(f'{region_shape.__class__.__name__} is not supported')
return aperture
[docs]def aperture2regions(aperture):
"""Convert a given ``photutils`` aperture to ``regions`` shape.
Parameters
----------
aperture : `photutils.aperture.Aperture`
An equivalent ``photutils`` aperture.
Returns
-------
region_shape : `regions.Region`
A supported ``regions`` shape.
Raises
------
NotImplementedError
The given ``photutils`` aperture is not supported.
ValueError
Invalid inputs.
Examples
--------
Translate a `photutils.aperture.CircularAperture` to `regions.CirclePixelRegion`:
>>> from photutils import CircularAperture
>>> from jdaviz.core.region_translators import aperture2regions
>>> aperture = CircularAperture((42, 43), 4.2)
>>> aperture2regions(aperture)
<CirclePixelRegion(center=PixCoord(x=42.0, y=43.0), radius=4.2)>
Also see
--------
regions2aperture
"""
if isinstance(aperture, CircularAperture):
region_shape = CirclePixelRegion(
center=positions2pixcoord(aperture.positions), radius=aperture.r)
elif isinstance(aperture, SkyCircularAperture):
region_shape = CircleSkyRegion(center=aperture.positions, radius=aperture.r)
elif isinstance(aperture, EllipticalAperture):
region_shape = EllipsePixelRegion(
center=positions2pixcoord(aperture.positions), width=aperture.a * 2,
height=aperture.b * 2, angle=theta2angle(aperture.theta))
elif isinstance(aperture, SkyEllipticalAperture):
region_shape = EllipseSkyRegion(
center=aperture.positions, width=aperture.a * 2, height=aperture.b * 2,
angle=aperture.theta)
elif isinstance(aperture, RectangularAperture):
region_shape = RectanglePixelRegion(
center=positions2pixcoord(aperture.positions), width=aperture.w, height=aperture.h,
angle=theta2angle(aperture.theta))
elif isinstance(aperture, SkyRectangularAperture):
region_shape = RectangleSkyRegion(
center=aperture.positions, width=aperture.w, height=aperture.h, angle=aperture.theta)
elif isinstance(aperture, CircularAnnulus):
region_shape = CircleAnnulusPixelRegion(
center=positions2pixcoord(aperture.positions), inner_radius=aperture.r_in,
outer_radius=aperture.r_out)
elif isinstance(aperture, SkyCircularAnnulus):
region_shape = CircleAnnulusSkyRegion(
center=aperture.positions, inner_radius=aperture.r_in, outer_radius=aperture.r_out)
elif isinstance(aperture, EllipticalAnnulus):
region_shape = EllipseAnnulusPixelRegion(
center=positions2pixcoord(aperture.positions), inner_width=aperture.a_in * 2,
inner_height=aperture.b_in * 2, outer_width=aperture.a_out * 2,
outer_height=aperture.b_out * 2, angle=theta2angle(aperture.theta))
elif isinstance(aperture, SkyEllipticalAnnulus):
region_shape = EllipseAnnulusSkyRegion(
center=aperture.positions, inner_width=aperture.a_in * 2,
inner_height=aperture.b_in * 2, outer_width=aperture.a_out * 2,
outer_height=aperture.b_out * 2, angle=aperture.theta)
elif isinstance(aperture, RectangularAnnulus):
region_shape = RectangleAnnulusPixelRegion(
center=positions2pixcoord(aperture.positions), inner_width=aperture.w_in,
inner_height=aperture.h_in, outer_width=aperture.w_out, outer_height=aperture.h_out,
angle=theta2angle(aperture.theta))
elif isinstance(aperture, SkyRectangularAnnulus):
region_shape = RectangleAnnulusSkyRegion(
center=aperture.positions, inner_width=aperture.w_in, inner_height=aperture.h_in,
outer_width=aperture.w_out, outer_height=aperture.h_out, angle=aperture.theta)
else: # pragma: no cover
raise NotImplementedError(f'{aperture.__class__.__name__} is not supported')
return region_shape
def positions2pixcoord(positions):
"""Convert ``photutils`` aperture positions to `~regions.PixCoord`
that is acceptable by ``regions`` shape.
"""
if positions.shape != (2, ):
raise ValueError('regions shape only accepts scalar x and y positions')
if isinstance(positions, u.Quantity):
pixcoord = PixCoord(x=positions[0].value, y=positions[1].value)
else:
pixcoord = PixCoord(x=positions[0], y=positions[1])
return pixcoord
def theta2angle(theta):
"""Convert ``photutils`` theta to ``regions`` angle."""
return Angle(theta, u.radian)