def test_scale(self):
xfac, yfac = 2, 3
tol = 5 # The low precision tolerance is for SpatiaLite
qs = Country.objects.annotate(scaled=functions.Scale('mpoly', xfac, yfac))
for country in qs:
for p1, p2 in zip(country.mpoly, country.scaled):
for r1, r2 in zip(p1, p2):
for c1, c2 in zip(r1.coords, r2.coords):
self.assertAlmostEqual(c1[0] * xfac, c2[0], tol)
self.assertAlmostEqual(c1[1] * yfac, c2[1], tol)
# Test float/Decimal values
qs = Country.objects.annotate(scaled=functions.Scale('mpoly', 1.5, Decimal('2.5')))
self.assertGreater(qs[0].scaled.area, qs[0].mpoly.area)
def _trans_scale(self, colname, deltax, deltay, xfactor, yfactor):
if connection.ops.spatialite:
return geofn.Scale(geofn.Translate(colname, deltax, deltay),
xfactor, yfactor)
else:
return TransScale(colname, deltax, deltay, xfactor, yfactor)
