python coding style and performance

Method of time counting

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import time

start = time.clock()

…

…

elapsed = (time.clock() - start)

print elapsed

 

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results

#----------------fibonaci-----------------
# run time 1.5e-05
#a, b = 0, 1
#v=[]
#while b < 4000000:
#    a, b = b, a+b
#    v.append(a)

# run time 4.2e-05
#v = [1,0];
#while v[0] < 1000000:
#    v=sum([v], [v[0]+v[1]])

# run time 3e-05
#v = [0,1];
#while v[-1] < 1000000:
#    v=v+ [v[-1]+v[-2]]

# run time 2.3e-05
#v=[0,1];
#while v[-1] < 1000000:
#    v[-1:-1],v[-1]=[v[-1]],v[-1]+v[-2]

# run time 1.5e-05
#v=[0,1];
#while v[-1] < 1000000:
#    v.append(v[-1]+v[-2])

the 5th is the best style, both fast and elegant.