def __init__(self, array, ilat=0, ilon=1, LatLon=None, shape=()):
'''Handle a C{NumPy} or C{Tuple} array as a sequence of C{LatLon} points.
'''
ais = ('ilat', ilat), ('ilon', ilon)
if len(shape) != 2 or shape[0] < 1 or shape[1] < len(ais):
raise IndexError('%s shape invalid: %r' % ('array', shape))
self._array = array
self._shape = shape
# check the point class
if LatLon is not None:
if isclass(LatLon) and all(
hasattr(LatLon, a) for a in LatLon_.__slots__):
self._LatLon = LatLon
else:
raise TypeError('%s invalid: %r' % ('LatLon', LatLon))
# check the attr indices
for n, (ai, i) in enumerate(ais):
if not isint(i):
raise TypeError('%s invalid: %r' % (ai, i))
i = int(i)
if not 0 <= i < shape[1]:
raise ValueError('%s invalid: %s' % (ai, i))
for aj, j in ais[:n]:
if int(j) == i:
raise ValueError('%s == %s == %s' % (ai, aj, i))
setattr(self, '_' + ai, i)
def subset(self, indices):
'''Return a subset of the C{NumPy} array.
@param indices: Row indices (C{range} or C{int}[]).
@note: A I{subset} is different from a I{slice} in 2 ways:
(a) the I{subset} is typically specified as a list of
(un-)ordered indices and (b) the I{subset} allocates
a new, separate C{NumPy} array while a I{slice} is
just an other I{view} of the original C{NumPy} array.
@return: Sub-array (C{numpy.array}).
@raise IndexError: Out-of-range I{indices} value.
@raise TypeError: If I{indices} is not a C{range} or C{int}[].
'''
if not issequence(indices, tuple): # NO tuple, only list
# and range work properly to get Numpy array sub-sets
raise TypeError('%s invalid: %s' % ('indices', type(indices)))
n = len(self)
for i, v in enumerate(indices):
if not isint(v):
raise TypeError('%s[%s] invalid: %r' % ('indices', i, v))
elif not 0 <= v < n:
raise IndexError('%s[%s] invalid: %r' % ('indices', i, v))
return self._subset(indices)
def precision(form, prec=None):
'''Set the default precison for a given F_ form.
@param form: L{F_D}, L{F_DM}, L{F_DMS}, L{F_DEG}, L{F_MIN},
L{F_SEC} or L{F_RAD} (C{str}).
@keyword prec: Optional number of decimal digits (0..9 or
C{None} for default). Trailing zero decimals
are stripped for I{prec} values of 1 and
above, but kept for negative I{prec} values.
@return: Previous precision (C{int}).
@raise ValueError: Invalid I{form} or I{prec} or beyond valid range.
'''
try:
p = _F_prec[form]
except KeyError:
raise ValueError('%s invalid: %s' % ('form', form))
if isint(prec):
if not -10 < prec < 10:
raise ValueError('%s invalid: %s' % ('prec', prec))
_F_prec[form] = prec
return p