Optimisation problem

[Skip Montanaro]

    gabor> x,y = 2,4 
    gabor> creates a tuple?

    gabor> i thought thatr x,y=2,4 is the same as x=2;y=4

Semantically, yes, it's the same, however, it makes an intermediate tuple of
the rhs in the process of performing the assignment.  The "dis" module is
your friend here:

    >>> import dis
    >>> def f(a,b):
    ...   c,d = a,b
    ... 
    >>> dis.dis(f)
      2           0 LOAD_FAST                0 (a)
                  3 LOAD_FAST                1 (b)
                  6 BUILD_TUPLE              2
                  9 UNPACK_SEQUENCE          2
                 12 STORE_FAST               2 (c)
                 15 STORE_FAST               3 (d)
                 18 LOAD_CONST               0 (None)
                 21 RETURN_VALUE        

-- 
Skip Montanaro - skip at pobox.com
http://www.mojam.com/
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