actuary77 wrote:
#================================================ # non-generator #================================================
def f1(afunc,aseed,n): values = [afunc(aseed)] for i in range(n-1): values.append(afunc(values[-1])) return values[-1]
_b=time() for _i in range(0,100): _y = f1(myfunc,seed,n)
Why do you do this? The whole point of this approach was to keep the intermediate results instead of recomputing them every time!
The point is to get some meaningful results when "timing" the function.
And why do you prepend underscores everywhere? It's bad Python style.
I prepend underscore to differentiate local,private variables vs. global variables. Do not want to create a conflict. It is my understanding that this is the Python style for local v. global variables.
_e=time() _t=_e-_b
print "f1 result: %r time: %f\n" % (_y,_t*10000.)
#================================================ # generator #================================================
def f2(afunc,aseed,n): v = myfunc(aseed) print v for i in range(n): yield v v = afunc(v)
def f2gen(i): for _i in range(1,n-1): f2(myfunc,seed,n) return f2(myfunc,seed,n) _b=time() for _i in range(0,cnt): _y = f2gen(_i) _e=time() _t=_e-_b print "f2gen result: %r time: %f\n" % (_y,_t*10000.)
==>
rec result: 10.005049999999988 time: 47669.999599
f1 result: 10.004999999999988 time: 399.999619
f2gen result: <generator object at 0x008D74E0> time: 30739.998817
I don't know how to get the generator to work correcly, I understand that the yield preserves the state of the funcion every time it is called. So in order to have myfunc called 50 times, the generator must be called 50 times, but it refuses to return a value. PEP 255 isn't helping me.
No, the generator call creates a generator object which you iterate over.
for value in f2(myfunc, seed, n): print value
If you absolutely need a list:
list(f2(myfunc, seed, n))
Thank you. -- http://mail.python.org/mailman/listinfo/python-list
