Say a vector V is a tuple of 3 numbers, not all zero. You want to normalize
it (scale all components by the same factor) so its magnitude is 1.
The usual way is something like this:
L = math.sqrt(V[0] * V[0] + V[1] * V[1] + V[2] * V[2])
V = (V[0] / L, V[1] / L, V[2] / L)
What I don’t like is having that intermediate variable L leftover after the
computation. Here’s how to do it in one step:
V = tuple \
(
x
/
math.sqrt
(
reduce(lambda a, b : a + b, (y * y for y in V), 0)
)
for x in V
)
which, incidentally, also works for vectors with dimensions other than 3.
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