def sumOf(nvectors, Vector=None, h=None, **Vector_kwds):
'''Return the vectorial sum of two or more n-vectors.
@arg nvectors: Vectors to be added (C{Nvector}[]).
@kwarg Vector: Optional class for the vectorial sum (C{Nvector})
or C{None}.
@kwarg h: Optional height, overriding the mean height (C{meter}).
@kwarg Vector_kwds: Optional, additional B{C{Vector}} keyword
arguments, ignored if C{B{Vector}=None}.
@return: Vectorial sum (B{C{Vector}}) or a L{Vector4Tuple}C{(x, y,
z, h)} if B{C{Vector}} is C{None}.
@raise VectorError: No B{C{nvectors}}.
'''
n, nvectors = len2(nvectors)
if n < 1:
raise VectorError(nvectors=n, txt=MISSING)
if h is None:
h = fsum(v.h for v in nvectors) / float(n)
if Vector is None:
r = _sumOf(nvectors, Vector=Vector3Tuple).to4Tuple(h)
else:
r = _sumOf(nvectors, Vector=Vector, h=h, **Vector_kwds)
return r
def sumOf(nvectors, Vector=Nvector, h=None, **kwds):
'''Return the vectorial sum of two or more n-vectors.
@param nvectors: Vectors to be added (L{Nvector}[]).
@keyword Vector: Optional class for the vectorial sum (L{Nvector}).
@keyword kwds: Optional, additional B{C{Vector}} keyword arguments.
@keyword h: Optional height, overriding the mean height (C{meter}).
@return: Vectorial sum (B{C{Vector}}).
@raise VectorError: No B{C{nvectors}}.
'''
n, nvectors = len2(nvectors)
if n < 1:
raise VectorError('no nvectors: %r' & (n, ))
if h is None:
h = fsum(v.h for v in nvectors) / float(n)
return _sumOf(nvectors, Vector=Vector, h=h, **kwds)
