autolens.Mask2D#
- class Mask2D[source]#
Bases:
Mask
A 2D mask, used for masking values which are associated with a a uniform rectangular grid of pixels.
When applied to 2D data with the same shape, values in the mask corresponding to
False
entries are unmasked and therefore used in subsequent calculations. .The ``Mask2D`, has in-built functionality which:
Maps data structures between two data representations: slim` (all unmasked
False
values in a 1Dndarray
) andnative
(all unmasked values in a 2D or 3Dndarray
).Has a
Geometry2D
object (defined by its (y,x)pixel scales
, (y,x)origin
andsub_size
) which defines how coordinates are converted from pixel units to scaled units.Associates Cartesian
Grid2D
objects of (y,x) coordinates with the data structure (e.g. a (y,x) grid of all unmasked pixels) via theDeriveGrid2D
object.This includes sub-grids, which perform calculations higher resolutions which are then binned up.
A detailed description of the 2D mask API is provided below.
SLIM DATA REPRESENTATION (sub-size=1)
Below is a visual illustration of a
Mask2D
, where a total of 10 pixels are unmasked (values areFalse
):x x x x x x x x x x x x x x x x x x x x This is an example ``Mask2D``, where: x x x x x x x x x x x x x x O O x x x x x = `True` (Pixel is masked and excluded from the array) x x x O O O O x x x O = `False` (Pixel is not masked and included in the array) x x x O O O O x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x
The mask pixel index’s are as follows (the positive / negative direction of the
Grid2D
objects associated with the mask are also shown on the y and x axes).<--- -ve x +ve --> x x x x x x x x x x ^ x x x x x x x x x x I x x x x x x x x x x I x x x x 0 1 x x x x +ve x x x 2 3 4 5 x x x y x x x 6 7 8 9 x x x -ve x x x x x x x x x x I x x x x x x x x x x I x x x x x x x x x x \/ x x x x x x x x x x
The
Mask2D
’sslim
data representation is anndarray
of shape [total_unmasked_pixels].For the
Mask2D
above theslim
representation therefore contains 10 entries and two examples of these entries are:mask[3] = the 4th unmasked pixel's value. mask[6] = the 7th unmasked pixel's value.
A Cartesian grid of (y,x) coordinates, corresponding to all
slim
values (e.g. unmasked pixels) is given bymask.derive_grid.masked.slim
.NATIVE DATA REPRESENTATION (sub_size=1)
Masked data represented as an an
ndarray
of shape [total_y_values, total_x_values], where all masked entries have values of 0.0.For the following mask:
x x x x x x x x x x x x x x x x x x x x This is an example ``Mask2D``, where: x x x x x x x x x x x x x x O O x x x x x = `True` (Pixel is masked and excluded from the array) x x x O O O O x x x O = `False` (Pixel is not masked and included in the array) x x x O O O O x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x
The mask has the following indexes:
<--- -ve x +ve --> x x x x x x x x x x ^ x x x x x x x x x x I x x x x x x x x x x I x x x x 0 1 x x x x +ve x x x 2 3 4 5 x x x y x x x 6 7 8 9 x x x -ve x x x x x x x x x x I x x x x x x x x x x I x x x x x x x x x x \/ x x x x x x x x x x
In the above array:
- mask[0,0] = True (it is masked) - mask[0,0] = True (it is masked) - mask[3,3] = True (it is masked) - mask[3,3] = True (it is masked) - mask[3,4] = False (not masked) - mask[3,5] = False (not masked) - mask[4,5] = False (not masked)
SLIM TO NATIVE MAPPING
The
Mask2D
has functionality which maps data between theslim
andnative
data representations.For the example mask above, the 1D
ndarray
given bymask.derive_indexes.slim_to_native
is:slim_to_native[0] = [3,4] slim_to_native[1] = [3,5] slim_to_native[2] = [4,3] slim_to_native[3] = [4,4] slim_to_native[4] = [4,5] slim_to_native[5] = [4,6] slim_to_native[6] = [5,3] slim_to_native[7] = [5,4] slim_to_native[8] = [5,5] slim_to_native[9] = [5,6]
SUB GRIDDING
If the
Mask2D
sub_size
is > 1, itsslim
andnative
data representations have entries corresponding to the values at the centre of every sub-pixel of each unmasked pixel.The sub-array indexes are ordered such that pixels begin from the first (top-left) sub-pixel in the first unmasked pixel. Indexes then go over the sub-pixels in each unmasked pixel, for every unmasked pixel.
Therefore, the shapes of the sub-array are as follows:
slim
representation: anndarray
of shape [total_unmasked_pixels*sub_size**2].native
representation: anndarray
of shape [total_y_values*sub_size, total_x_values*sub_size].
Below is a visual illustration of a sub array. Indexing of each sub-pixel goes from the top-left corner. In contrast to the array above, our illustration below restricts the mask to just 2 pixels, to keep the illustration brief.
x x x x x x x x x x x x x x x x x x x x This is an example ``Mask2D``, where: x x x x x x x x x x x x x x x x x x x x x = `True` (Pixel is masked and excluded from lens) x 0 0 x x x x x x x O = `False` (Pixel is not masked and included in lens) x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x
If
sub_size=2
, each unmasked pixel has 4 (2x2) sub-pixel values. For the example above, pixels 0 and 1 each have 4 values which map toslim
representation as follows:Pixel 0 - (2x2): slim[0] = value of first sub-pixel in pixel 0. 0 1 slim[1] = value of first sub-pixel in pixel 1. 2 3 slim[2] = value of first sub-pixel in pixel 2. slim[3] = value of first sub-pixel in pixel 3. Pixel 1 - (2x2): slim[4] = value of first sub-pixel in pixel 0. 4 5 slim[5] = value of first sub-pixel in pixel 1. 6 7 slim[6] = value of first sub-pixel in pixel 2. slim[7] = value of first sub-pixel in pixel 3.
For the
native
data representation we get the following mappings:Pixel 0 - (2x2): native[8, 2] = value of first sub-pixel in pixel 0. 0 1 native[8, 3] = value of first sub-pixel in pixel 1. 2 3 native[9, 2] = value of first sub-pixel in pixel 2. native[9, 3] = value of first sub-pixel in pixel 3. Pixel 1 - (2x2): native[10, 4] = value of first sub-pixel in pixel 0. 4 5 native[10, 5] = value of first sub-pixel in pixel 1. 6 7 native[11, 4] = value of first sub-pixel in pixel 2. native[11, 5] = value of first sub-pixel in pixel 3. Other entries (all masked sub-pixels are zero): native[0, 0] = 0.0 (it is masked, thus zero) native[15, 12] = 0.0 (it is masked, thus zero)
If we used a sub_size of 3, for pixel 0 we we would create a 3x3 sub-array:
slim[0] = value of first sub-pixel in pixel 0. slim[1] = value of first sub-pixel in pixel 1. slim[2] = value of first sub-pixel in pixel 2. 0 1 2 slim[3] = value of first sub-pixel in pixel 3. 3 4 5 slim[4] = value of first sub-pixel in pixel 4. 6 7 8 slim[5] = value of first sub-pixel in pixel 5. slim[6] = value of first sub-pixel in pixel 6. slim[7] = value of first sub-pixel in pixel 7. slim[8] = value of first sub-pixel in pixel 8.
- Parameters
mask – The ndarray of shape [total_y_pixels, total_x_pixels] containing the bool’s representing the mask, where False signifies an entry is unmasked and used in calculations.
pixel_scales – The (y,x) scaled units to pixel units conversion factors of every pixel. If this is input as a float, it is converted to a (float, float) structure.
origin – The (y,x) scaled units origin of the mask’s coordinate system.
Methods
all
Returns True if all elements evaluate to True.
Create a mask where all pixels are False and therefore unmasked.
any
Returns True if any of the elements of a evaluate to True.
argmax
Return indices of the maximum values along the given axis.
argmin
Return indices of the minimum values along the given axis.
argpartition
Returns the indices that would partition this array.
argsort
Returns the indices that would sort this array.
astype
Copy of the array, cast to a specified type.
byteswap
Swap the bytes of the array elements
choose
Use an index array to construct a new array from a set of choices.
Returns a Mask2D (see Mask2D.__new__) where all False entries are within a circle of input radius.
Returns a Mask2D (see Mask2D.__new__) where all False entries are within an annulus of input inner radius and outer radius.
Returns a Mask2D (see Mask2D.__new__) where all False entries are within an inner circle and second outer circle, forming an inverse annulus.
clip
Return an array whose values are limited to
[min, max]
.compress
Return selected slices of this array along given axis.
conj
Complex-conjugate all elements.
conjugate
Return the complex conjugate, element-wise.
copy
Return a copy of the array.
cumprod
Return the cumulative product of the elements along the given axis.
cumsum
Return the cumulative sum of the elements along the given axis.
diagonal
Return specified diagonals.
dot
dump
Dump a pickle of the array to the specified file.
dumps
Returns the pickle of the array as a string.
Returns a Mask2D (see Mask2D.__new__) where all False entries are within an ellipse.
Returns a Mask2D (see Mask2D.__new__) where all False entries are within an elliptical annulus of input inner and outer scaled major-axis and centre.
fill
Fill the array with a scalar value.
flatten
Return a copy of the array collapsed into one dimension.
flip_hdu_for_ds9
Loads the image from a .fits file.
Returns a Mask2D (see Mask2D.__new__) where all False entries are defined from an input list of list of pixel coordinates.
Returns an
Mask2D
by from a PrimaryHDU object which has been loaded via astropy.fitsgetfield
Returns a field of the given array as a certain type.
item
Copy an element of an array to a standard Python scalar and return it.
itemset
Insert scalar into an array (scalar is cast to array's dtype, if possible)
mask_new_sub_size_from
Returns the mask on the same scaled coordinate system but with a sub-grid of an inputsub_size.
max
Return the maximum along a given axis.
mean
Returns the average of the array elements along given axis.
min
Return the minimum along a given axis.
newbyteorder
Return the array with the same data viewed with a different byte order.
nonzero
Return the indices of the elements that are non-zero.
Write the 2D Mask to a .fits file.
partition
Rearranges the elements in the array in such a way that the value of the element in kth position is in the position it would be in a sorted array.
prod
Return the product of the array elements over the given axis
ptp
Peak to peak (maximum - minimum) value along a given axis.
put
Set
a.flat[n] = values[n]
for all n in indices.ravel
Return a flattened array.
repeat
Repeat elements of an array.
reshape
Returns an array containing the same data with a new shape.
resize
Change shape and size of array in-place.
round
Return a with each element rounded to the given number of decimals.
searchsorted
Find indices where elements of v should be inserted in a to maintain order.
setfield
Put a value into a specified place in a field defined by a data-type.
setflags
Set array flags WRITEABLE, ALIGNED, WRITEBACKIFCOPY, respectively.
sort
Sort an array in-place.
squeeze
Remove axes of length one from a.
std
Returns the standard deviation of the array elements along given axis.
sum
Return the sum of the array elements over the given axis.
swapaxes
Return a view of the array with axis1 and axis2 interchanged.
take
Return an array formed from the elements of a at the given indices.
tobytes
Construct Python bytes containing the raw data bytes in the array.
tofile
Write array to a file as text or binary (default).
tolist
Return the array as an
a.ndim
-levels deep nested list of Python scalars.tostring
A compatibility alias for tobytes, with exactly the same behavior.
trace
Return the sum along diagonals of the array.
transpose
Returns a view of the array with axes transposed.
Map a padded 1D array of values to its original 2D array, trimming all edge values.
For a padded grid and psf, compute an unmasked blurred image from an unmasked unblurred image.
var
Returns the variance of the array elements, along given axis.
view
New view of array with the same data.
Attributes
T
The transposed array.
base
Base object if memory is from some other object.
ctypes
An object to simplify the interaction of the array with the ctypes module.
data
Python buffer object pointing to the start of the array's data.
derive_grid
- rtype
DeriveGrid2D
derive_indexes
A property that is only computed once per instance and then replaces itself with an ordinary attribute.
derive_mask
- rtype
DeriveMask2D
dimensions
- rtype
dtype
Data-type of the array's elements.
flags
Information about the memory layout of the array.
flat
A 1-D iterator over the array.
Return the 2D geometry of the mask, representing its uniform rectangular grid of (y,x) coordinates defined by its
shape_native
.The mask as a HDU object, which can be output to a .fits file.
imag
The imaginary part of the array.
is_all_false
Returns False if all pixels in a mask are False, else returns True.
is_all_true
Returns True if all pixels in a mask are True, else returns False.
itemsize
Length of one array element in bytes.
mask_centre
native
Returns the data structure in its native format which contains all unmaksed values to the native dimensions.
nbytes
Total bytes consumed by the elements of the array.
ndim
Number of array dimensions.
pixel_scale
For a mask with dimensions two or above check that are pixel scales are the same, and if so return this single value as a float.
pixel_scale_header
Returns the pixel scale of the mask as a header dictionary, which can be written to a .fits file.
pixel_scales
pixels_in_mask
The total number of unmasked pixels (values are False) in the mask.
real
The real part of the array.
shape
Tuple of array dimensions.
shape_native
The (y,x) shape corresponding to the extent of unmasked pixels that go vertically and horizontally across the mask.
shape_slim
The 1D shape of the mask, which is equivalent to the total number of unmasked pixels in the mask.
size
Number of elements in the array.
strides
Tuple of bytes to step in each dimension when traversing an array.
sub_fraction
The fraction of the area of a pixel every sub-pixel contains.
sub_length
The total number of sub-pixels in a give pixel,
sub_pixels_in_mask
The total number of unmasked sub-pixels (values are False) in the mask.
sub_shape_native
sub_shape_slim
The 1D shape of the mask's sub-grid, which is equivalent to the total number of unmasked pixels in the mask.
zoom_centre
The scaled-grid of (y,x) coordinates of every pixel.
zoom_offset_pixels
zoom_offset_scaled
The zoomed rectangular region corresponding to the square encompassing all unmasked values.
zoom_shape_native
- property geometry: Geometry2D#
Return the 2D geometry of the mask, representing its uniform rectangular grid of (y,x) coordinates defined by its
shape_native
.- Return type
Geometry2D
- classmethod all_false(shape_native, pixel_scales, sub_size=1, origin=(0.0, 0.0), invert=False)[source]#
Create a mask where all pixels are False and therefore unmasked.
- Parameters
shape_native (
Tuple
[int
,int
]) – The 2D shape of the mask that is created.pixel_scales (
Union
[Tuple
[float
],Tuple
[float
,float
],float
]) – The (y,x) scaled units to pixel units conversion factors of every pixel. If this is input as a float, it is converted to a (float, float) structure.sub_size (
int
) – The size (sub_size x sub_size) of each unmasked pixels sub-array.origin (
Tuple
[float
,float
]) – The (y,x) scaled units origin of the mask’s coordinate system.invert (
bool
) – If True, the bool’s of the input mask are inverted, for example False’s become True and visa versa.
- Return type
- classmethod circular(shape_native, radius, pixel_scales, sub_size=1, origin=(0.0, 0.0), centre=(0.0, 0.0), invert=False)[source]#
Returns a Mask2D (see Mask2D.__new__) where all False entries are within a circle of input radius.
The radius and centre are both input in scaled units.
- Parameters
shape_native (
Tuple
[int
,int
]) – The (y,x) shape of the mask in units of pixels.radius (
float
) – The radius in scaled units of the circle within which pixels are False and unmasked.pixel_scales (
Union
[Tuple
[float
],Tuple
[float
,float
],float
]) – The (y,x) scaled units to pixel units conversion factors of every pixel. If this is input as a float, it is converted to a (float, float) structure.sub_size (
int
) – The size (sub_size x sub_size) of each unmasked pixels sub-array.origin (
Tuple
[float
,float
]) – The (y,x) scaled units origin of the mask’s coordinate system.centre (
Tuple
[float
,float
]) – The (y,x) scaled units centre of the circle used to mask pixels.invert (
bool
) – If True, the bool’s of the input mask are inverted, for example False’s become True and visa versa.
- Return type
- classmethod circular_annular(shape_native, inner_radius, outer_radius, pixel_scales, sub_size=1, origin=(0.0, 0.0), centre=(0.0, 0.0), invert=False)[source]#
Returns a Mask2D (see Mask2D.__new__) where all False entries are within an annulus of input inner radius and outer radius.
The inner_radius, outer_radius and centre are all input in scaled units.
- Parameters
shape_native (
Tuple
[int
,int
]) – The (y,x) shape of the mask in units of pixels.inner_radius (
float
) – The inner radius in scaled units of the annulus within which pixels are False and unmasked.outer_radius (
float
) – The outer radius in scaled units of the annulus within which pixels are False and unmasked.pixel_scales (
Union
[Tuple
[float
],Tuple
[float
,float
],float
]) – The (y,x) scaled units to pixel units conversion factors of every pixel. If this is input as a float, it is converted to a (float, float) structure.sub_size (
int
) – The size (sub_size x sub_size) of each unmasked pixels sub-array.origin (
Tuple
[float
,float
]) – The (y,x) scaled units origin of the mask’s coordinate system.centre (
Tuple
[float
,float
]) – The (y,x) scaled units centre of the annulus used to mask pixels.invert (
bool
) – If True, the bool’s of the input mask are inverted, for example False’s become True and visa versa.
- Return type
- classmethod circular_anti_annular(shape_native, inner_radius, outer_radius, outer_radius_2, pixel_scales, sub_size=1, origin=(0.0, 0.0), centre=(0.0, 0.0), invert=False)[source]#
Returns a Mask2D (see Mask2D.__new__) where all False entries are within an inner circle and second outer circle, forming an inverse annulus.
The inner_radius, outer_radius, outer_radius_2 and centre are all input in scaled units.
- Parameters
shape_native (
Tuple
[int
,int
]) – The (y,x) shape of the mask in units of pixels.inner_radius (
float
) – The inner radius in scaled units of the annulus within which pixels are False and unmasked.outer_radius (
float
) – The first outer radius in scaled units of the annulus within which pixels are True and masked.outer_radius_2 (
float
) – The second outer radius in scaled units of the annulus within which pixels are False and unmasked and outside of which all entries are True and masked.pixel_scales (
Union
[Tuple
[float
],Tuple
[float
,float
],float
]) – The (y,x) scaled units to pixel units conversion factors of every pixel. If this is input as a float, it is converted to a (float, float) structure.sub_size (
int
) – The size (sub_size x sub_size) of each unmasked pixels sub-array.origin (
Tuple
[float
,float
]) – The (y,x) scaled units origin of the mask’s coordinate system.centre (
Tuple
[float
,float
]) – The (y,x) scaled units centre of the anti-annulus used to mask pixels.invert (
bool
) – If True, the bool’s of the input mask are inverted, for example False’s become True and visa versa.
- Return type
- classmethod elliptical(shape_native, major_axis_radius, axis_ratio, angle, pixel_scales, sub_size=1, origin=(0.0, 0.0), centre=(0.0, 0.0), invert=False)[source]#
Returns a Mask2D (see Mask2D.__new__) where all False entries are within an ellipse.
The major_axis_radius, and centre are all input in scaled units.
- Parameters
shape_native (
Tuple
[int
,int
]) – The (y,x) shape of the mask in units of pixels.major_axis_radius (
float
) – The major-axis in scaled units of the ellipse within which pixels are unmasked.axis_ratio (
float
) – The axis-ratio of the ellipse within which pixels are unmasked.angle (
float
) –- The rotation angle of the ellipse within which pixels are unmasked, (counter-clockwise from the positive
x-axis).
pixel_scales (
Union
[Tuple
[float
],Tuple
[float
,float
],float
]) – The (y,x) scaled units to pixel units conversion factors of every pixel. If this is input as a float, it is converted to a (float, float) structure.sub_size (
int
) – The size (sub_size x sub_size) of each unmasked pixels sub-array.origin (
Tuple
[float
,float
]) – The (y,x) scaled units origin of the mask’s coordinate system.centre (
Tuple
[float
,float
]) – The (y,x) scaled units centred of the ellipse used to mask pixels.invert (
bool
) – If True, the bool’s of the input mask are inverted, for example False’s become True and visa versa.
- Return type
- classmethod elliptical_annular(shape_native, inner_major_axis_radius, inner_axis_ratio, inner_phi, outer_major_axis_radius, outer_axis_ratio, outer_phi, pixel_scales, sub_size=1, origin=(0.0, 0.0), centre=(0.0, 0.0), invert=False)[source]#
Returns a Mask2D (see Mask2D.__new__) where all False entries are within an elliptical annulus of input inner and outer scaled major-axis and centre.
The outer_major_axis_radius, inner_major_axis_radius and centre are all input in scaled units.
- Parameters
(int (shape_native) – The (y,x) shape of the mask in units of pixels.
int) – The (y,x) shape of the mask in units of pixels.
pixel_scales (
Union
[Tuple
[float
],Tuple
[float
,float
],float
]) – The scaled units to pixel units conversion factor of each pixel.inner_major_axis_radius (
float
) – The major-axis in scaled units of the inner ellipse within which pixels are masked.inner_axis_ratio (
float
) – The axis-ratio of the inner ellipse within which pixels are masked.inner_phi (
float
) – The rotation angle of the inner ellipse within which pixels are masked, (counter-clockwise from the positive x-axis).outer_major_axis_radius (
float
) – The major-axis in scaled units of the outer ellipse within which pixels are unmasked.outer_axis_ratio (
float
) – The axis-ratio of the outer ellipse within which pixels are unmasked.outer_phi (
float
) – The rotation angle of the outer ellipse within which pixels are unmasked, (counter-clockwise from the positive x-axis).sub_size (
int
) – The size (sub_size x sub_size) of each unmasked pixels sub-array.origin (
Tuple
[float
,float
]) – The (y,x) scaled units origin of the mask’s coordinate system.centre (
Tuple
[float
,float
]) – The (y,x) scaled units centre of the elliptical annuli used to mask pixels.invert (
bool
) – If True, the bool’s of the input mask are inverted, for example False’s become True and visa versa.
- Return type
- classmethod from_pixel_coordinates(shape_native, pixel_coordinates, pixel_scales, sub_size=1, origin=(0.0, 0.0), buffer=0, invert=False)[source]#
Returns a Mask2D (see Mask2D.__new__) where all False entries are defined from an input list of list of pixel coordinates.
These may be buffed via an input buffer, whereby all entries in all 8 neighboring directions by this amount.
- Parameters
(int (shape_native) – The (y,x) shape of the mask in units of pixels.
int) – The (y,x) shape of the mask in units of pixels.
pixel_coordinates ([[int, int]]) – The input lists of 2D pixel coordinates where False entries are created.
pixel_scales – The scaled units to pixel units conversion factor of each pixel.
sub_size – The size (sub_size x sub_size) of each unmasked pixels sub-array.
origin – The (y,x) scaled units origin of the mask’s coordinate system.
buffer – All input pixel_coordinates are buffed with False entries in all 8 neighboring directions by this amount.
invert – If True, the bool’s of the input mask are inverted, for example False’s become True and visa versa.
- classmethod from_fits(file_path, pixel_scales, hdu=0, sub_size=1, origin=(0.0, 0.0), resized_mask_shape=None)[source]#
Loads the image from a .fits file.
- Parameters
file_path (
Union
[Path
,str
]) – The full path of the fits file.hdu (
int
) – The HDU number in the fits file containing the image image.(float (pixel_scales or) – The scaled units to pixel units conversion factor of each pixel.
float) – The scaled units to pixel units conversion factor of each pixel.
sub_size (
int
) – The size (sub_size x sub_size) of each unmasked pixels sub-array.origin (
Tuple
[float
,float
]) – The (y,x) scaled units origin of the mask’s coordinate system.
- Return type
- classmethod from_primary_hdu(primary_hdu, sub_size=1, origin=(0.0, 0.0))[source]#
Returns an
Mask2D
by from a PrimaryHDU object which has been loaded via astropy.fitsThis assumes that the header of the PrimaryHDU contains an entry named PIXSCALE which gives the pixel-scale of the array.
For a full description of
Mask2D
objects, including a description of theslim
andnative
attribute used by the API, see theMask2D class API documentation
.- Parameters
primary_hdu (
PrimaryHDU
) – The PrimaryHDU object which has already been loaded from a .fits file via astropy.fits and contains the array data and the pixel-scale in the header with an entry named PIXSCALE.sub_size (
int
) – The size (sub_size x sub_size) of each unmasked pixels sub-array.origin (
Tuple
[float
,float
]) – The (y,x) scaled units origin of the coordinate system.
Examples
from astropy.io import fits import autoarray as aa # Make Mask2D with sub_size 1. primary_hdu = fits.open("path/to/file.fits") array_2d = aa.Mask2D.from_primary_hdu( primary_hdu=primary_hdu, sub_size=1 )
import autoarray as aa # Make Mask2D with sub_size 2. # (It is uncommon that a sub-gridded array would be loaded from # a .fits, but the API support its). primary_hdu = fits.open("path/to/file.fits") array_2d = aa.Mask2D.from_primary_hdu( primary_hdu=primary_hdu, sub_size=2 )
- Return type
- trimmed_array_from(padded_array, image_shape)[source]#
Map a padded 1D array of values to its original 2D array, trimming all edge values.
- Parameters
padded_array – A 1D array of values which were computed using a padded grid
- Return type
- unmasked_blurred_array_from(padded_array, psf, image_shape)[source]#
For a padded grid and psf, compute an unmasked blurred image from an unmasked unblurred image.
This relies on using the lens dataset’s padded-grid, which is a grid of (y,x) coordinates which extends over the entire image as opposed to just the masked region.
- Parameters
psf (aa.Kernel2D) – The PSF of the image used for convolution.
unmasked_image_1d – The 1D unmasked image which is blurred.
- Return type
- property hdu_for_output: PrimaryHDU#
The mask as a HDU object, which can be output to a .fits file.
The header of the HDU is used to store the pixel_scale of the array, which is used by the Array2D.from_hdu.
This method is used in other projects (E.g. PyAutoGalaxy, PyAutoLens) to conveniently output the array to .fits files.
- Return type
The HDU containing the data and its header which can then be written to .fits.
- output_to_fits(file_path, overwrite=False)[source]#
Write the 2D Mask to a .fits file.
Before outputting a NumPy array, the array may be flipped upside-down using np.flipud depending on the project config files. This is for Astronomy projects so that structures appear the same orientation as .fits files loaded in DS9.
- Parameters
file_path – The full path of the file that is output, including the file name and .fits extension.
overwrite – If True and a file already exists with the input file_path the .fits file is overwritten. If False, an error is raised.
- Return type
None
Examples
mask = Mask2D(mask=np.full(shape=(5,5), fill_value=False)) mask.output_to_fits(file_path=’/path/to/file/filename.fits’, overwrite=True)
- property shape_native_masked_pixels: Tuple[int, int]#
The (y,x) shape corresponding to the extent of unmasked pixels that go vertically and horizontally across the mask.
For example, if a mask is primarily surrounded by True entries, and there are 15 False entries going vertically and 12 False entries going horizontally in the central regions of the mask, then shape_masked_pixels=(15,12).