diff options
Diffstat (limited to 'lib/skyline.py')
| -rw-r--r-- | lib/skyline.py | 159 |
1 files changed, 143 insertions, 16 deletions
diff --git a/lib/skyline.py b/lib/skyline.py index 2cc70c1..8a9755f 100644 --- a/lib/skyline.py +++ b/lib/skyline.py @@ -91,13 +91,14 @@ from copy import copy, deepcopy # THIRD-PARTY import pyfits from stwcs import wcsutil +from stwcs.distortion.utils import output_wcs # LOCAL from .polygon import SphericalPolygon __all__ = ['SkyLine'] -__version__ = '0.2a' -__vdate__ = '12-Jun-2012' +__version__ = '0.3a' +__vdate__ = '20-Jun-2012' class SkyLineMember(object): @@ -111,9 +112,6 @@ class SkyLineMember(object): Parameters ---------- - self: obj - SkyLineMember instance. - fname: str FITS image. @@ -123,12 +121,12 @@ class SkyLineMember(object): """ self._fname = fname self._ext = ext - self._polygon = SphericalPolygon.from_wcs( - wcsutil.HSTWCS(fname, ext=ext)) + self._wcs = wcsutil.HSTWCS(fname, ext=ext) + self._polygon = SphericalPolygon.from_wcs(self.wcs) def __repr__(self): - return 'SkyLineMember(%r, %r, %r)' % (self.fname, self.ext, - self.polygon) + return '%s(%r, %r, %r, %r)' % (self.__class__.__name__, self.fname, + self.ext, self.wcs, self.polygon) @property def fname(self): @@ -139,6 +137,10 @@ class SkyLineMember(object): return self._ext @property + def wcs(self): + return self._wcs + + @property def polygon(self): return self._polygon @@ -150,9 +152,6 @@ class SkyLine(object): Parameters ---------- - self: obj - `SkyLine` instance. - fname: str FITS image. `None` to create empty `SkyLine`. @@ -174,7 +173,8 @@ class SkyLine(object): # Put mosaic of all the chips in SkyLine if len(self.members) > 0: - self.polygon = SphericalPolygon.multi_union([m.polygon for m in self.members]) + self.polygon = SphericalPolygon.multi_union( + [m.polygon for m in self.members]) else: self.polygon = SphericalPolygon([]) @@ -183,8 +183,8 @@ class SkyLine(object): if what in ('from_radec', 'from_cone', 'from_wcs', 'multi_union', 'multi_intersection', '_find_new_inside',): - raise AttributeError('\'SkyLine\' object has no attribute \'%s\'' % - what) + raise AttributeError('\'%s\' object has no attribute \'%s\'' % + (self.__class__.__name__, what)) else: return getattr(self.polygon, what) @@ -192,7 +192,8 @@ class SkyLine(object): return deepcopy(self) def __repr__(self): - return 'SkyLine(%r, %r)' % (self.polygon, self.members) + return '%s(%r, %r)' % (self.__class__.__name__, + self.polygon, self.members) @property def polygon(self): @@ -223,6 +224,14 @@ class SkyLine(object): if v not in self._members: self._members.append(v) + def to_wcs(self): + """ + Combine WCS objects from all `members` and return a + new WCS object. + + """ + return output_wcs([m.wcs for m in self.members]) + def _find_members(self, given_members): """ Find `SkyLineMember` in *given_members* that is in @@ -288,3 +297,121 @@ class SkyLine(object): newcls.polygon = self.intersection(other) newcls.members = newcls._find_members(self.members + other.members) return newcls + + def find_max_overlap(self, skylines): + """ + Find `SkyLine` from a list of *skylines* that overlaps + the most with *self*. + + Parameters + ---------- + skylines: list + A list of `SkyLine` instances. + + Returns + ------- + max_skyline: `SkyLine` instance or `None` + `SkyLine` that overlaps the most or `None` if no + overlap found. + + max_overlap_area: float + Area of intersection. + + """ + max_skyline = None + max_overlap_area = 0.0 + + for next_s in skylines: + overlap_area = self.intersection(next_s).area() + + if overlap_area > max_overlap_area: + max_overlap_area = overlap_area + max_skyline = next_s + + return max_skyline, max_overlap_area + + @staticmethod + def max_overlap_pair(skylines): + """ + Find a pair of skylines with maximum overlap. + + Parameters + ---------- + skylines: list + A list of `SkyLine` instances. + + Returns + ------- + max_pair: tuple + Pair of `SkyLine` instances with max overlap + among given *skylines*. If no overlap found, + return `None`. + + """ + max_pair = None + max_overlap_area = 0.0 + + for i in xrange(len(skylines) - 1): + curr_s = skylines[i] + next_s, i_area = curr_s.find_max_overlap(skylines[i+1:]) + + if i_area > max_overlap_area: + max_overlap_area = i_area + max_pair = (curr_s, next_s) + + return max_pair + + @classmethod + def mosaic(cls, skylines): + """ + Mosaic all overlapping *skylines*. + + Parameters + ---------- + skylines: list + A list of `SkyLine` instances. + + Returns + ------- + mosaic: `SkyLine` instance or `None` + Union of all overlapping *skylines*, or `None` if + no overlap found. + + included: list + List of image names added to `mosaic` in the order + of addition. + + excluded: list + List of image names excluded because they do not + overlap with `mosaic`. + + """ + out_order = [] + excluded = [] + + starting_pair = cls.max_overlap_pair(skylines) + if starting_pair is None: + return starting_pair, out_order, excluded + + remaining = list(skylines) + + s1, s2 = starting_pair + mosaic = s1.add_image(s2) + out_order = [s1.members[0].fname, s2.members[0].fname] + remaining.remove(s1) + remaining.remove(s2) + + while len(remaining) > 0: + next_skyline, i_area = mosaic.find_max_overlap(remaining) + + if next_skyline is None: + for r in remaining: + excluded.append(r.members[0].fname) + break + + new_mos = mosaic.add_image(next_skyline) + mosaic = new_mos + out_order.append(next_skyline.members[0].fname) + remaining.remove(next_skyline) + + return mosaic, out_order, excluded |