From d2fd4f0dc6d4b84c5af0be032a387594349211cd Mon Sep 17 00:00:00 2001 From: Justin Bronn Date: Mon, 3 Dec 2007 18:15:57 +0000 Subject: [PATCH] gis: added additional units (including WKT aliases) and the `unit_attname` class method to `Distance`. git-svn-id: http://code.djangoproject.com/svn/django/branches/gis@6865 bcc190cf-cafb-0310-a4f2-bffc1f526a37 --- django/contrib/gis/measure.py | 161 +++++++++++++++++++---- django/contrib/gis/tests/test_measure.py | 26 +++- 2 files changed, 154 insertions(+), 33 deletions(-) diff --git a/django/contrib/gis/measure.py b/django/contrib/gis/measure.py index 75ab53474c..b04d8c8f29 100644 --- a/django/contrib/gis/measure.py +++ b/django/contrib/gis/measure.py @@ -39,15 +39,84 @@ from decimal import Decimal class Distance(object): UNITS = { - 'm': 1.0, - 'km': 1000.0, - 'mi': 1609.344, + 'chain' : 20.1168, + 'chain_benoit' : 20.116782, + 'chain_sears' : 20.1167645, + 'british_chain_benoit' : 20.1167824944, + 'british_chain_sears' : 20.1167651216, + 'british_chain_sears_truncated' : 20.116756, + 'cm' : 0.01, + 'british_ft' : 0.304799471539, + 'british_yd' : 0.914398414616, + 'degree' : 0.0174532925199, + 'clarke_ft' : 0.3047972654, + 'clarke_link' : 0.201166195164, + 'fathom' : 1.8288, 'ft': 0.3048, - 'yd': 0.9144, + 'german_m' : 1.0000135965, + 'grad' : 0.0157079632679, + 'gold_coast_ft' : 0.304799710181508, + 'indian_yd' : 0.914398530744, + 'in' : 0.0254, + 'km': 1000.0, + 'link' : 0.201168, + 'link_benoit' : 0.20116782, + 'link_sears' : 0.20116765, + 'm': 1.0, + 'mi': 1609.344, + 'mm' : 0.001, 'nm': 1852.0, - } + 'nm_uk' : 1853.184, + 'rod' : 5.0292, + 'sears_yd' : 0.91439841, + 'survey_ft' : 0.304800609601, + 'um' : 0.000001, + 'yd': 0.9144, + } + + # Unit aliases for `UNIT` terms encountered in Spatial Reference WKT. + ALIAS = { + 'centimeter' : 'cm', + 'foot' : 'ft', + 'inches' : 'in', + 'kilometer' : 'km', + 'kilometre' : 'km', + 'meter' : 'm', + 'metre' : 'm', + 'micrometer' : 'um', + 'micrometre' : 'um', + 'millimeter' : 'mm', + 'millimetre' : 'mm', + 'mile' : 'mi', + 'yard' : 'yd', + 'British chain (Benoit 1895 B)' : 'british_chain_benoit', + 'British chain (Sears 1922)' : 'british_chain_sears', + 'British chain (Sears 1922 truncated)' : 'british_chain_sears_truncated', + 'British foot (Sears 1922)' : 'british_ft', + 'British yard (Sears 1922)' : 'british_yd', + "Clarke's Foot" : 'clarke_ft', + "Clarke's foot" : 'clarke_ft', + "Clarke's link" : 'clarke_link', + 'Chain (Benoit)' : 'chain_benoit', + 'Chain (Sears)' : 'chain_sears', + 'Decimal Degree' : 'degree', + 'Foot (International)' : 'ft', + 'German legal metre' : 'german_m', + 'Gold Coast foot' : 'gold_coast_ft', + 'Indian yard' : 'indian_yd', + 'Link (Benoit)': 'link_benoit', + 'Link (Sears)': 'link_sears', + 'Nautical Mile' : 'nm', + 'Nautical Mile (UK)' : 'nm_uk', + 'US survey foot' : 'survey_ft', + 'U.S. Foot' : 'survey_ft', + 'Yard (Indian)' : 'indian_yd', + 'Yard (Sears)' : 'sears_yd' + } + REV_ALIAS = dict((value, key) for key, value in ALIAS.items()) def __init__(self, default_unit=None, **kwargs): + # The base unit is in meters. self.m = 0.0 self._default_unit = 'm' @@ -55,8 +124,21 @@ class Distance(object): if unit in self.UNITS: self.m += self.UNITS[unit] * value self._default_unit = unit + elif unit in self.ALIAS: + u = self.ALIAS[unit] + self.m += self.UNITS[u] * value + self._default_unit = u else: - raise AttributeError("Unknown unit type: " + unit) + lower = unit.lower() + if lower in self.UNITS: + self.m += self.UNITS[lower] * value + self._default_unit = lower + elif lower in self.ALIAS: + u = self.ALIAS[lower] + self.m += self.UNITS[u] * value + self._default_unit = u + else: + raise AttributeError('Unknown unit type: %s' % unit) if default_unit and isinstance(default_unit, str): self._default_unit = default_unit @@ -65,13 +147,13 @@ class Distance(object): if name in self.UNITS: return self.m / self.UNITS[name] else: - raise AttributeError("Unknown unit type: " + name) + raise AttributeError('Unknown unit type: %s' % name) def __repr__(self): - return "Distance(%s=%s)" % (self._default_unit, getattr(self, self._default_unit)) + return 'Distance(%s=%s)' % (self._default_unit, getattr(self, self._default_unit)) def __str__(self): - return "%s %s" % (getattr(self, self._default_unit), self._default_unit) + return '%s %s' % (getattr(self, self._default_unit), self._default_unit) def __cmp__(self, other): if isinstance(other, Distance): @@ -83,27 +165,27 @@ class Distance(object): if isinstance(other, Distance): return Distance(default_unit=self._default_unit, m=(self.m + other.m)) else: - raise TypeError("Distance must be added with Distance") + raise TypeError('Distance must be added with Distance') def __iadd__(self, other): if isinstance(other, Distance): self.m += other.m return self else: - raise TypeError("Distance must be added with Distance") + raise TypeError('Distance must be added with Distance') def __sub__(self, other): if isinstance(other, Distance): return Distance(default_unit=self._default_unit, m=(self.m - other.m)) else: - raise TypeError("Distance must be subtracted from Distance") + raise TypeError('Distance must be subtracted from Distance') def __isub__(self, other): if isinstance(other, Distance): self.m -= other.m return self else: - raise TypeError("Distance must be subtracted from Distance") + raise TypeError('Distance must be subtracted from Distance') def __mul__(self, other): if isinstance(other, (int, float, long, Decimal)): @@ -111,32 +193,53 @@ class Distance(object): elif isinstance(other, Distance): return Area(default_unit='sq_' + self._default_unit, sq_m=(self.m * other.m)) else: - raise TypeError("Distance must be multiplied with number or Distance") + raise TypeError('Distance must be multiplied with number or Distance') def __imul__(self, other): if isinstance(other, (int, float, long, Decimal)): self.m *= float(other) return self else: - raise TypeError("Distance must be multiplied with number") + raise TypeError('Distance must be multiplied with number') def __div__(self, other): if isinstance(other, (int, float, long, Decimal)): return Distance(default_unit=self._default_unit, m=(self.m / float(other))) else: - raise TypeError("Distance must be divided with number") + raise TypeError('Distance must be divided with number') def __idiv__(self, other): if isinstance(other, (int, float, long, Decimal)): self.m /= float(other) return self else: - raise TypeError("Distance must be divided with number") + raise TypeError('Distance must be divided with number') def __nonzero__(self): return bool(self.m) + @classmethod + def unit_attname(cls, unit_str): + """ + Retrieves the unit attribute name for the given unit string. + For example, if the given unit string is 'metre', 'm' would be returned. + An exception is raised if an attribute cannot be found. + """ + lower = unit_str.lower() + + if unit_str in cls.UNITS: + return unit_str + elif lower in cls.UNITS: + return lower + elif unit_str in cls.ALIAS: + return cls.ALIAS[unit_str] + elif lower in cls.ALIAS: + return cls.ALIAS[lower] + else: + raise Exception('Could not find a unit keyword associated with "%s"' % unit_str) + class Area(object): + # TODO: Add units from above. UNITS = { 'sq_m': 1.0, 'sq_km': 1000000.0, @@ -155,7 +258,7 @@ class Area(object): self.sq_m += self.UNITS[unit] * value self._default_unit = unit else: - raise AttributeError("Unknown unit type: " + unit) + raise AttributeError('Unknown unit type: ' + unit) if default_unit: self._default_unit = default_unit @@ -164,13 +267,13 @@ class Area(object): if name in self.UNITS: return self.sq_m / self.UNITS[name] else: - raise AttributeError("Unknown unit type: " + name) + raise AttributeError('Unknown unit type: ' + name) def __repr__(self): - return "Area(%s=%s)" % (self._default_unit, getattr(self, self._default_unit)) + return 'Area(%s=%s)' % (self._default_unit, getattr(self, self._default_unit)) def __str__(self): - return "%s %s" % (getattr(self, self._default_unit), self._default_unit) + return '%s %s' % (getattr(self, self._default_unit), self._default_unit) def __cmp__(self, other): if isinstance(other, Area): @@ -182,53 +285,53 @@ class Area(object): if isinstance(other, Area): return Area(default_unit=self._default_unit, sq_m=(self.sq_m + other.sq_m)) else: - raise TypeError("Area must be added with Area") + raise TypeError('Area must be added with Area') def __iadd__(self, other): if isinstance(other, Area): self.sq_m += other.sq_m return self else: - raise TypeError("Area must be added with Area") + raise TypeError('Area must be added with Area') def __sub__(self, other): if isinstance(other, Area): return Area(default_unit=self._default_unit, sq_m=(self.sq_m - other.sq_m)) else: - raise TypeError("Area must be subtracted from Area") + raise TypeError('Area must be subtracted from Area') def __isub__(self, other): if isinstance(other, Area): self.sq_m -= other.sq_m return self else: - raise TypeError("Area must be subtracted from Area") + raise TypeError('Area must be subtracted from Area') def __mul__(self, other): if isinstance(other, (int, float, long, Decimal)): return Area(default_unit=self._default_unit, sq_m=(self.sq_m * float(other))) else: - raise TypeError("Area must be multiplied with number") + raise TypeError('Area must be multiplied with number') def __imul__(self, other): if isinstance(other, (int, float, long, Decimal)): self.sq_m *= float(other) return self else: - raise TypeError("Area must be multiplied with number") + raise TypeError('Area must be multiplied with number') def __div__(self, other): if isinstance(other, (int, float, long, Decimal)): return Area(default_unit=self._default_unit, sq_m=(self.sq_m / float(other))) else: - raise TypeError("Area must be divided with number") + raise TypeError('Area must be divided with number') def __idiv__(self, other): if isinstance(other, (int, float, long, Decimal)): self.sq_m /= float(other) return self else: - raise TypeError("Area must be divided with number") + raise TypeError('Area must be divided with number') def __nonzero__(self): return bool(self.sq_m) diff --git a/django/contrib/gis/tests/test_measure.py b/django/contrib/gis/tests/test_measure.py index 3c71cc4834..43bc8ae691 100644 --- a/django/contrib/gis/tests/test_measure.py +++ b/django/contrib/gis/tests/test_measure.py @@ -14,11 +14,22 @@ class DistanceTest(unittest.TestCase): d = Distance(m=100) self.assertEqual(d.m, 100) - d = D(m=100) - self.assertEqual(d.m, 100) - + d1, d2, d3 = D(m=100), D(meter=100), D(metre=100) + for d in (d1, d2, d3): + self.assertEqual(d.m, 100) + d = D(nm=100) self.assertEqual(d.m, 185200) + + y1, y2, y3 = D(yd=100), D(yard=100), D(Yard=100) + for d in (y1, y2, y3): + self.assertEqual(d.yd, 100) + + mm1, mm2 = D(millimeter=1000), D(MiLLiMeTeR=1000) + for d in (mm1, mm2): + self.assertEqual(d.m, 1.0) + self.assertEqual(d.mm, 1000.0) + def testInitInvalid(self): "Testing initialisation from invalid units" @@ -152,6 +163,13 @@ class DistanceTest(unittest.TestCase): self.assertEqual(repr(d1), 'Distance(m=100.0)') self.assertEqual(repr(d2), 'Distance(km=3.5)') + def testUnitAttName(self): + "Testing the `unit_attname` class method" + unit_tuple = [('Yard', 'yd'), ('Nautical Mile', 'nm'), ('German legal metre', 'german_m'), + ('Indian yard', 'indian_yd'), ('Chain (Sears)', 'chain_sears'), ('Chain', 'chain')] + for nm, att in unit_tuple: + self.assertEqual(att, D.unit_attname(nm)) + class AreaTest(unittest.TestCase): "Testing the Area object" @@ -312,4 +330,4 @@ def run(verbosity=2): unittest.TextTestRunner(verbosity=verbosity).run(suite()) if __name__=="__main__": - run() \ No newline at end of file + run()