"""

A multi-dimensional ``Vector`` class, take 5

"""

from array import array

import math

import reprlib

import numbers

class Vector:

typecode = 'd'

def __init__(self, components):

self._components = array(self.typecode, components)

def __len__(self):

return len(self._components)

def __iter__(self):

return iter(self._components)

def __abs__(self):

return math.sqrt(sum(x * x for x in self))

def __eq__(self, other):

return (len(self) == len(other) and

all(a == b for a, b in zip(self, other)))

def __str__(self):

return str(tuple(self))

def __repr__(self):

components = reprlib.repr(self._components)

components = components[components.find('['):-1]

return 'Vector({})'.format(components)

def __getitem__(self, index):

cls = type(self)

if isinstance(index, slice):

return cls(self._components[index])

elif isinstance(index, numbers.Integral):

return self._components[index]

else:

msg = '{cls.__name__} indices must be integers'

raise TypeError(msg.format(cls=cls))

def __mul__(self, scalar):

if isinstance(scalar, numbers.Real):

return Vector(n * scalar for n in self)

else:

return NotImplemented

def __rmul__(self, scalar):

return self * scalar

# ...

def __matmul__(self, other): # Python 3.5 only!

try:

return sum(a * b for a, b in zip(self, other))

except TypeError:

return NotImplemented

def __rmatmul__(self, other):

return self @ other # syntax error if Python < 3.5