Op 2011-04-01 16:04, vm schreef:
I'm analyzing some data in python. I have stumbled across unusual problem:
I have the function...
def fun1(params_used_below_except_lk_and_lk2):
lk = 0.0
lk2 = 0.0
for raw_data, hist, freq in raw_data_hist_list:
lk2 = lk2 + fun2(some_constants_and_params_from_this_scope)
q = fun2(same_args_as_before)
lk = lk + q
print lk, lk2
For some set of input parameters, This function with specific input
prints out the same constant twice (as expected):
15377.7424582 15377.7424582 (twice the same value)
If I comment out lines q = fun2 and lk = lk + q, fun1, with the same
parameters, prints:
0.0 3.3469936856
First value is expected, but I cannot understand how come the second
value is different in these two cases!
Let's have a look at your source:
fun1 source:
def process_measurements_beta_lk(x, raw_data_hist_list):
lk = 0.0
lk2 = 0.0
(p,q,loc,scale) = x
for raw_data, hist, freq in raw_data_hist_list:
lk2 = lk2 + get_beta_func_fit_quality_hist_lk('beta',
(p,q,loc,scale), raw_data, hist)
#q = get_beta_func_fit_quality_hist_lk('beta',(p,q,loc,scale),
raw_data, hist)
# lk = lk + q
print lk, lk2
retrun lk
The lie with lk2 = uses the value of q. In the version with commented
lines, that value is never changed, while it is changed each iteration
in the version with the lines uncommented.
--
The saddest aspect of life right now is that science gathers knowledge
faster than society gathers wisdom.
-- Isaac Asimov
Roel Schroeven
--
http://mail.python.org/mailman/listinfo/python-list
