Source code for reducer.astro_gui

from __future__ import (division, print_function, absolute_import,
                        unicode_literals)

from collections import OrderedDict
import os
import warnings

from astropy.modeling import models
import ccdproc
from astropy.extern import six
from astropy.stats import median_absolute_deviation

import numpy as np

from . import gui

import ipywidgets as widgets
from traitlets import Any, link

__all__ = [
    'Reduction',
    'Combiner',
    'CosmicRaySettings',
    'Slice',
    'CalibrationStep',
    'BiasSubtract',
    'DarkSubtract',
    'FlatCorrect',
    'Overscan',
    'Trim'
]

DEFAULT_IMAGE_UNIT = "adu"

# The dictionary below is used to map the dtype of the image being
# reduced to the dtype of the output. The assumption is that the output
# is typically some kind of floating point, but that there is no need
# for very high precision output given relatively low resolution
# input.
REDUCE_IMAGE_DTYPE_MAPPING = {
    'uint8': 'float32',
    'int8': 'float32',
    'uint16': 'float32',
    'int16': 'float32',
    'float32': 'float32',
    'uint32': 'float64',
    'int32': 'float64',
    'float64': 'float64'
}

# The limit below is used  by the combining function to decide whether or
# not the image should be broken up into chunks.
DEFAULT_MEMORY_LIMIT = 4e9  # roughly 4GB


class ReducerBase(gui.ToggleGo):
    """
    Base class for reduction and combination widgets that provides a couple
    of properties common to both.

    Parameters
    ----------

    apply_to : dict
        Key-value pair(s) that select images that will be acted on by the
        widget.

    destination : str
        Directory in which reduced images will be stored.
    """
    def __init__(self, *arg, **kwd):
        self._apply_to = kwd.pop('apply_to', None)
        self._destination = kwd.pop('destination', None)
        super(ReducerBase, self).__init__(*arg, **kwd)

    @property
    def destination(self):
        return self._destination

    @property
    def apply_to(self):
        return self._apply_to


[docs]class Reduction(ReducerBase): """ Primary widget for performing a logical reduction step (e.g. dark subtraction or flat correction). """ def __init__(self, *arg, **kwd): allow_flat = kwd.pop('allow_flat', True) allow_dark = kwd.pop('allow_dark', True) allow_bias = kwd.pop('allow_bias', True) allow_cosmic_ray = kwd.pop('allow_cosmic_ray', False) allow_copy = kwd.pop('allow_copy_only', True) self.image_collection = kwd.pop('input_image_collection', None) self._master_source = kwd.pop('master_source', None) super(Reduction, self).__init__(*arg, **kwd) self._overscan = Overscan(description='Subtract overscan?') self._trim = Trim(description='Trim (specify region to keep)?') self._cosmic_ray = CosmicRaySettings() self._bias_calib = BiasSubtract(master_source=self._master_source) self._dark_calib = DarkSubtract(master_source=self._master_source) self._flat_calib = FlatCorrect(master_source=self._master_source) if allow_copy: self._copy_only = CopyFiles() self.add_child(self._copy_only) else: self._copy_only = None self.add_child(self._overscan) self.add_child(self._trim) if allow_bias: self.add_child(self._bias_calib) if allow_dark: self.add_child(self._dark_calib) if allow_flat: self.add_child(self._flat_calib) if allow_cosmic_ray: self.add_child(self._cosmic_ray) if self._copy_only: self._copy_only._state_monitor.on_trait_change( self._disable_all_others(), str('value') )
[docs] def action(self): if not self.image_collection: raise ValueError("No images to reduce") self.progress_bar.visible = True self.progress_bar.layout.visbility = 'visible' self.progress_bar.layout.display = 'flex' # Refresh in case files have been added since the widget was created. self.image_collection.refresh() # Only refresh the master_source if it exists. No need to error check # the main image_collection because a sensible error is raised if it # does not exist. if self._master_source: self._master_source.refresh() # Suppress warnings that come up here...mostly about HIERARCH keywords warnings.filterwarnings('ignore') try: n_files = \ len(self.image_collection.files_filtered(**self.apply_to)) current_file = 0 for hdu, fname in self.image_collection.hdus(return_fname=True, save_location=self.destination, **self.apply_to): current_file += 1 try: unit = hdu.header['BUNIT'] except KeyError: unit = DEFAULT_IMAGE_UNIT ccd = ccdproc.CCDData(hdu.data, meta=hdu.header, unit=unit) for child in self.container.children: if not child.toggle.value: # Nothing to do for this child, so keep going. continue ccd = child.action(ccd) input_dtype = hdu.data.dtype.name hdu_tmp = ccd.to_hdu()[0] hdu.header = hdu_tmp.header hdu.data = hdu_tmp.data desired_dtype = REDUCE_IMAGE_DTYPE_MAPPING[str(input_dtype)] if desired_dtype != hdu.data.dtype: hdu.data = hdu.data.astype(desired_dtype) # Workaround to ensure uint16 images are handled properly. if 'bzero' in hdu.header: # Check for the unsigned int16 case, and if our data type # is no longer uint16, delete BZERO and BSCALE header_unsigned_int = ((hdu.header['bscale'] == 1) and (hdu.header['bzero'] == 32768)) if (header_unsigned_int and (hdu.data.dtype != np.dtype('uint16'))): del hdu.header['bzero'], hdu.header['bscale'] self.progress_bar.description = \ ("Processed file {} of {}".format(current_file, n_files)) self.progress_bar.value = current_file/n_files except IOError: print("One or more of the reduced images already exists. Delete " "those files and try again. This notebook will NOT " "overwrite existing files.") finally: self.progress_bar.visible = False self.progress_bar.layout.display = 'none'
def _disable_all_others(self): if not self._copy_only: return None def handler(): all_but_copy = [c for c in self.container.children if c is not self._copy_only] if self._copy_only._state_monitor.value: for child in all_but_copy: print(child.description) child.disabled = True else: for child in all_but_copy: child.disabled = False return handler
class Clipping(gui.ToggleContainer): """docstring for Clipping""" def __init__(self, *args, **kwd): super(Clipping, self).__init__(*args, **kwd) self._min_max = gui.ToggleMinMax(description="Clip by min/max?") self._sigma_clip = gui.ToggleMinMax(description="Sigma clip?") self.add_child(self._min_max) self.add_child(self._sigma_clip) self.format() @property def min_max(self): if self._min_max.toggle.value: return self._min_max else: return False @property def sigma_clip(self): if self._sigma_clip.toggle.value: return self._sigma_clip else: return False @property def is_sane(self): # If not selected, sanity state does not matter... if not self.toggle.value: return None # It makes no sense to have selected clipping but not a clipping # method.... sanity = (self._min_max.toggle.value or self._sigma_clip.toggle.value) # For min_max clipping, maximum must be greater than minimum. if self._min_max.toggle.value: sanity = sanity and (self._min_max.max > self._min_max.min) # For sigma clipping there is no relationship between maximum # and minimum because both are number of deviations above/below # central value, but values of 0 make no sense if self._sigma_clip.toggle.value: sanity = (sanity and self._sigma_clip.min != 0 and self._sigma_clip.max != 0) return sanity def format(self): super(Clipping, self).format() self._sigma_clip.format() self._min_max.format() def override_str_factory(obj): """ Factory to create a new class for an IPYthon widget in which the ``__str__`` method is overridden with the widgets description and value. Parameters ---------- obj : object An IPython widget instance Returns ------- new_object : IPython widget with string method overridden """ from copy import copy def new_str_method(self): return ": ".join([str(self.description), str(self.value)]) new_instance = copy(obj) original_class = type(obj) new_class = type(original_class.__name__, (original_class,), {'__str__': new_str_method}) new_instance.__class__ = new_class return new_instance class Combine(gui.ToggleContainer): """ Represent combine choices and actions. """ def __init__(self, *args, **kwd): super(Combine, self).__init__(*args, **kwd) self._combine_option = override_str_factory( widgets.ToggleButtons(description="Combination method:", options=['Average', 'Median'], style={'description_width': 'initial'}) ) self.add_child(self._combine_option) self._scaling = gui.ToggleContainer(description="Scale before combining?") scal_desc = "Which should scale to same value?" self._scale_by = override_str_factory( widgets.RadioButtons(description=scal_desc, options=['mean', 'median'], style={'description_width': 'initial'}) ) self._scaling.add_child(self._scale_by) self.add_child(self._scaling) @property def method(self): return self._combine_option.value @property def scaling_func(self): if not self._scaling.toggle.value: return None if self._scale_by.value == 'mean': return lambda arr: 1/np.ma.average(arr) elif self._scale_by.value == 'median': return lambda arr: 1/np.ma.median(arr) @property def is_sane(self): if not self.toggle.value: return None else: # In this case, the only options presented are sane ones return True class GroupBy(gui.ToggleContainer): def __init__(self, *args, **kwd): self._image_source = kwd.pop('image_source', None) input_value = kwd.pop('value', '') super(GroupBy, self).__init__(*args, **kwd) self._keyword_list = override_str_factory( widgets.Text(description='Keywords (comma-separated)', value=input_value, style={'description_width': 'initial'}) ) self.add_child(self._keyword_list) if input_value: self.toggle.value = True @property def value(self): return self._keyword_list.value def groups(self, apply_to): if not (self.toggle.value and self.value): # Return an empty dictionary by default if there is no grouping return [{}] # remember, the rest is really an else to the above... from copy import deepcopy keywords = [k.strip() for k in self.value.split(',')] # Yuck...need to use an internal method to get the mask I need. tmp_coll = deepcopy(self._image_source) tmp_coll._find_keywords_by_values(**apply_to) mask = tmp_coll.summary_info['file'].mask # Note the logical not below; mask indicates which values # should be EXCLUDED. filtered_table = tmp_coll.summary_info[~mask] grouped_table = filtered_table.group_by(keywords) combine_groups = grouped_table.groups.keys group_list = [] for row in combine_groups: d = {c: row[c] for c in combine_groups.colnames} group_list.append(d) #print(group_list) return group_list
[docs]class Combiner(ReducerBase): """ Widget for displaying options for ccdproc.Combiner. Parameters ---------- description : str, optional Text displayed next to check box for selecting options. """ def __init__(self, *args, **kwd): group_by_in = kwd.pop('group_by', '') self._image_source = kwd.pop('image_source', None) self._file_base_name = kwd.pop('file_name_base', 'master') super(Combiner, self).__init__(*args, **kwd) self._clipping_widget = \ Clipping(description="Clip before combining?") self._combine_method = \ Combine(description="Combine images?") self.add_child(self._clipping_widget) self.add_child(self._combine_method) self._group_by = GroupBy(description='Group by:', value=group_by_in, image_source=self._image_source) self.add_child(self._group_by) self._combined = None @property def combined(self): """ The combined image. """ return self._combined @property def image_source(self): return self._image_source @property def is_sane(self): # Start with the default sanity determination... sanity = super(Combiner, self).is_sane # ...but flip to insane if combination is not selected. sanity = sanity and self._combine_method.toggle.value return sanity
[docs] def format(self): super(Combiner, self).format() self._clipping_widget.format() # self.progress_bar.add_class('active progress-info progress-striped') # ADD STRIPES self.progress_bar.bar_style = 'info' # Yuck. _dom_classes is a tuple, so make it a list, append to it, then # reset. Similar to the way add_child handles children. old_dom_classes = list(self.progress_bar._dom_classes) if 'prgress-striped' not in old_dom_classes: old_dom_classes.append('progress-striped') self.progress_bar._dom_classes = old_dom_classes
[docs] def action(self): self.progress_bar.visible = True self.progress_bar.value = 1.0 self.progress_bar.layout.visbility = 'visible' self.progress_bar.layout.display = 'flex' # Refresh image collection in case files were added after widget was # created. self.image_source.refresh() groups_to_combine = self._group_by.groups(self.apply_to) n_groups = len(groups_to_combine) for idx, combo_group in enumerate(groups_to_combine): self.progress_bar.description = \ ("Processing {} of {} " "(may take several minutes)".format(idx + 1, n_groups)) combined = self._action_for_one_group(combo_group) name_addons = ['_'.join([str(k), str(v)]) for k, v in six.iteritems(combo_group)] fname = [self._file_base_name] fname.extend(name_addons) fname = '_'.join(fname) + '.fit' dest_path = os.path.join(self.destination, fname) combined.write(dest_path) self._combined = combined self.progress_bar.visible = False self.progress_bar.layout.display = 'none'
def _action_for_one_group(self, filter_dict=None): combined_dict = self.apply_to.copy() if filter_dict is not None: combined_dict.update(filter_dict) file_list = [os.path.join(self.image_source.location, f) for f in self.image_source.files_filtered(**combined_dict)] combine_keyword_args = { 'minmax_clip': self._clipping_widget.min_max, 'sigma_clip': self._clipping_widget.sigma_clip, } if self._combine_method.method == 'Average': combine_keyword_args['method'] = 'average' elif self._combine_method.method == 'Median': combine_keyword_args['method'] = 'median' if combine_keyword_args['minmax_clip']: combine_keyword_args['minmax_clip_min'] = \ self._clipping_widget.min_max.min combine_keyword_args['minmax_clip_max'] = \ self._clipping_widget.min_max.max if combine_keyword_args['sigma_clip']: combine_keyword_args['sigma_clip_low_thresh'] = \ self._clipping_widget.sigma_clip.min combine_keyword_args['sigma_clip_low_thresh'] = \ self._clipping_widget.sigma_clip.min combine_keyword_args['sigma_clip_func'] = np.ma.median combine_keyword_args['sigma_clip_dev_func'] = \ median_absolute_deviation if self._combine_method.scaling_func: combine_keyword_args['scale'] = self._combine_method.scaling_func combined = ccdproc.combine(file_list, mem_limit=DEFAULT_MEMORY_LIMIT, **combine_keyword_args) sample_image = ccdproc.CCDData.read(file_list[0]) combined.header = sample_image.header combined.header['master'] = True if combined.data.dtype != sample_image.dtype: combined.data = np.array(combined.data, dtype=sample_image.dtype) try: if isinstance(combined.uncertainty.array, np.ma.masked_array): combined.uncertainty.array = np.array(combined.uncertainty.array) except AttributeError: pass # Do not keep the mask or uncertainty if the data has neither if sample_image.mask is None and sample_image.uncertainty is None: combined.mask = None combined.uncertainty = None return combined
[docs]class CosmicRaySettings(gui.ToggleContainer): def __init__(self, *args, **kwd): descript = kwd.pop('description', 'Clean cosmic rays?') kwd['description'] = descript super(CosmicRaySettings, self).__init__(*args, **kwd) cr_choices = override_str_factory( widgets.Dropdown(description='Method:', options=['median [not connected yet]', 'LACosmic [coming soon]']) ) self.add_child(cr_choices)
[docs] def display(self): from IPython.display import display display(self)
class AxisSelection(widgets.Box): """docstring for AxisSelection""" def __init__(self, *args, **kwd): super(AxisSelection, self).__init__(*args, **kwd) self.layout.display = 'flex' values = OrderedDict() values["axis 0"] = 0 values["axis 1"] = 1 drop_desc = ('Region is all of') self._pre = self._make_pre_widget(drop_desc, values) style = {'description_width': 'initial'} self._start_text = widgets.Label('and along the other axis from ') self._start = widgets.IntText(style=style) self._stop_text = widgets.Label('up to (but not including):') self._stop = widgets.IntText(style=style) self.children = [ self._pre, self._start_text, self._start, self._stop_text, self._stop ] def __str__(self): gob = [' '.join([child.description, str(child.value)]) for child in self.children] return ' '.join(gob) def _make_pre_widget(self, description, values): box = widgets.HBox() box.description = description text = widgets.Label(value=description) style = {'button_width': 'initial'} toggles = widgets.ToggleButtons(options=values, style=style) # Vertically align text and toggles. box.layout.align_items = 'center' box.children = [text, toggles] box.add_traits(value=Any(sync=True, default_value=toggles.value)) link((box, 'value'), (toggles, 'value')) return box @property def full_axis(self): return self._pre.children[1].value @property def start(self): return self._start.value @property def stop(self): return self._stop.value def format(self): # self._start.set_css('width', '30px') self._start.layout.width = '5em' # self._stop.set_css('width', '30px') self._stop.layout.width = '5em'
[docs]class Slice(gui.ToggleContainer): def __init__(self, *arg, **kwd): self.images = kwd.pop('images', []) super(Slice, self).__init__(*arg, **kwd) self._axis_selection = AxisSelection() self.add_child(self._axis_selection) for child in self._axis_selection.children: self._child_notify_parent_on_change(child)
[docs] def format(self): super(Slice, self).format() hbox_these = [self._axis_selection] # [self, self.container] for hbox in hbox_these: hbox.orientation = 'horizontal' self._axis_selection.format()
@property def is_sane(self): """ Determine whether combination of settings is at least remotely plausible. """ # If the Slice is not selected, return None if not self.toggle.value: return None # Stop value must be larger than start (i.e. slice must contain at # least one row/column). sanity = self._axis_selection.stop > self._axis_selection.start return sanity
class MasterImageSource(widgets.Box): """docstring for ReductionSource""" def __init__(self): super(MasterImageSource, self).__init__(description="Reduction choices") self._source_list = [('Created in this notebook', 'notebook'), ('File on disk', 'disk')] self._source = widgets.ToggleButtons(description='Source:', options=self._source_list) self._source.observe(self._file_select_visibility(), str('index')) self._file_select = widgets.Dropdown(description="Select file:", options=["Not working yet"]) self._file_select.layout.display = 'none' self.children = [self._source, self._file_select] def __str__(self): return self._source.description + ' ' + str(self._source.value) def _file_select_visibility(self): def file_visibility(change): value = change['new'] self._file_select.visible = self._source_list[value][1] == 'disk' if self._file_select.visible: self._file_select.layout.display = 'flex' self._file_select.layout.visbility = 'visible' else: self._file_select.layout.display = 'none' return file_visibility
[docs]class CalibrationStep(gui.ToggleContainer): """ Represents a calibration step that corresponds to a ccdproc command. Parameters ---------- None """ def __init__(self, *args, **kwd): self._master_source = kwd.pop('master_source', None) super(CalibrationStep, self).__init__(*args, **kwd) self._settings = MasterImageSource() self.add_child(self._settings) self._image_cache = {} self._match_on = [] @property def match_on(self): """ List of keywords whose values should match in the image being calibated and the calibration image. """ return self._match_on @match_on.setter def match_on(self, value): self._match_on = value def _master_image(self, selector, closest=None): """ Identify appropriate master and return as `ccdproc.CCDData`. Parameters ---------- selector : dict-like Dictionary of key/value pairs that uniquely select the appropriate master image. closest : str, optional Name of keyword from ``selector`` whose value needs only be closest to the value in the dictionary instead of being an exact match. """ if not self._master_source: raise RuntimeError("No source provided for master.") file_name = self._master_source.files_filtered(master=True, **selector) if len(file_name) > 1: raise RuntimeError("Well, crap. Should only be one master but " "found these matches: " "{} for {}.".format(file_name, selector)) elif len(file_name) == 0: if closest is None: raise RuntimeError("No master found for {}".format(selector)) else: new_select = selector.copy() del new_select[closest] file_name = self._master_source.files_filtered(master=True, **new_select) master_table = self._master_source.summary_info min_dist = 1e20 for name in file_name: match = master_table['file'] == name distance = abs(master_table[closest][match] - selector[closest]) if distance <= min_dist: best_match = name min_dist = distance file_name = [best_match] file_name = file_name[0] path = os.path.join(self._master_source.location, file_name) try: return self._image_cache[path] except KeyError: # Try getting the unit form the FITS file, but force it to ADU try: self._image_cache[path] = ccdproc.CCDData.read(path) except ValueError: self._image_cache[path] = \ ccdproc.CCDData.read(path, unit=DEFAULT_IMAGE_UNIT) return self._image_cache[path]
class CopyFiles(gui.ToggleContainer): """ Just copy images to destination directory without modifying the file. Useful, for example, if the bias frames have no overscan and do not need to be trimmed. """ def __init__(self, **kwd): desc = kwd.pop('description', 'Copy without any other action?') kwd['description'] = desc super(CopyFiles, self).__init__(**kwd) def action(self, ccd): return ccd
[docs]class BiasSubtract(CalibrationStep): """ Subtract bias from an image using widget settings. """ def __init__(self, bias_image=None, **kwd): desc = kwd.pop('description', 'Subtract bias?') kwd['description'] = desc super(BiasSubtract, self).__init__(**kwd)
[docs] def action(self, ccd): select_dict = {'imagetyp': 'bias'} master = self._master_image(select_dict) return ccdproc.subtract_bias(ccd, master)
class DarkScaleSetting(widgets.Box): """docstring for DarkScaleSetting""" def __init__(self, *arg, **kwd): super(DarkScaleSetting, self).__init__(*arg, **kwd) value_dict = {'Yes': True, 'No': False} self._scale = override_str_factory(\ widgets.ToggleButtons(\ description='Scale dark by exposure time (if needed)', options=value_dict, value=False)) self.children = [self._scale] @property def scale(self): return self._scale.value def __str__(self): return str(self._scale)
[docs]class DarkSubtract(CalibrationStep): """ Subtract dark from an image using widget settings. """ def __init__(self, bias_image=None, **kwd): desc = kwd.pop('description', 'Subtract Dark?') kwd['description'] = desc super(DarkSubtract, self).__init__(**kwd) self.match_on = ['exposure'] self._scale = DarkScaleSetting() self.add_child(self._scale)
[docs] def action(self, ccd): from astropy import units as u select_dict = {'imagetyp': 'dark'} for keyword in self.match_on: if keyword in select_dict: raise ValueError("Keyword {} already has a value set".format(keyword)) select_dict[keyword] = ccd.header[keyword] if self._scale.scale: master = self._master_image(select_dict, closest=self.match_on[0]) if not 'subbias' in master.meta: raise RuntimeError("Bias has not been subtracted from dark, " "so cannot scale dark") else: master = self._master_image(select_dict) return ccdproc.subtract_dark(ccd, master, exposure_time='exposure', exposure_unit=u.second, scale=self._scale.scale)
[docs]class FlatCorrect(CalibrationStep): """ Subtract dark from an image using widget settings. """ def __init__(self, bias_image=None, **kwd): desc = kwd.pop('description', 'Flat correct?') kwd['description'] = desc super(FlatCorrect, self).__init__(**kwd) self.match_on = ['filter']
[docs] def action(self, ccd): select_dict = {'imagetyp': 'flat'} for keyword in self.match_on: if keyword in select_dict: raise ValueError("Keyword {} already has a value set".format(keyword)) select_dict[keyword] = ccd.header[keyword] master = self._master_image(select_dict) return ccdproc.flat_correct(ccd, master)
class PolynomialDropdown(widgets.Dropdown): def __init__(self): poly_values = OrderedDict() poly_values["Order 0/one term (constant)"] = 1 poly_values["Order 1/two term (linear)"] = 2 poly_values["Order 2/three team (quadratic)"] = 3 poly_values["Are you serious? Higher order is silly."] = None super(PolynomialDropdown, self).__init__( description="Choose fit", options=poly_values, value=1) def __str__(self): for k, v in six.iteritems(self.options): if v == self.value: return k
[docs]class Overscan(Slice): """docstring for Overscan""" def __init__(self, *arg, **kwd): super(Overscan, self).__init__(*arg, **kwd) poly_desc = "Fit polynomial to overscan?" self._polyfit = gui.ToggleContainer(description=poly_desc) poly_dropdown = PolynomialDropdown() self._polyfit.add_child(poly_dropdown) self.add_child(self._polyfit)
[docs] def format(self): super(Overscan, self).format() self._polyfit.format() self._polyfit.orientation = 'horizontal'
@property def is_sane(self): # Am I even active? If not, return None if not self.toggle.value: return None # See what the Slice thinks.... sanity = super(Overscan, self).is_sane if self._polyfit.toggle.value: poly_dropdown = self._polyfit.container.children[0] sanity = sanity and (poly_dropdown.value is not None) return sanity @property def polynomial_order(self): # yuck return self._polyfit.container.children[0].value
[docs] def action(self, ccd): """ Subtract overscan from image based on settings. Parameters ---------- ccd : `ccdproc.CCDData` Image to be reduced. """ if not self.toggle.value: pass whole_axis = slice(None, None) partial_axis = slice(self._axis_selection.start, self._axis_selection.stop) # create a two-element list which will be filled with the appropriate # slice based on the widget settings. if self._axis_selection.full_axis == 0: first_axis = whole_axis second_axis = partial_axis oscan_axis = 1 else: first_axis = partial_axis second_axis = whole_axis oscan_axis = 0 if self._polyfit.toggle.value: poly_model = models.Polynomial1D(self.polynomial_order) else: poly_model = None reduced = ccdproc.subtract_overscan(ccd, overscan=ccd[first_axis, second_axis], overscan_axis=oscan_axis, model=poly_model) return reduced
[docs]class Trim(Slice): """ Controls and action for trimming a widget. """ def __init__(self, *arg, **kwd): super(Trim, self).__init__(*arg, **kwd) # TODO: remove the line below sooner rather than later. self._axis_selection._stop.value = 3073
[docs] def action(self, ccd): """ Trim an image to bounds given in the widget. Returns ------- trimmed : `ccdproc.CCDData` Trimmed image. """ # Don't do anything if not activated if not self.toggle.value: pass whole_axis = slice(None, None) partial_axis = slice(self._axis_selection.start, self._axis_selection.stop) # create a two-element list which will be filled with the appropriate # slice based on the widget settings. if self._axis_selection.full_axis == 0: trimmed = ccdproc.trim_image(ccd[whole_axis, partial_axis]) else: trimmed = ccdproc.trim_image(ccd[partial_axis, whole_axis]) return trimmed