python - pandas edit a cell value with itertuples -


i speed code, don't use double for: code:

    c in range(0, n-1):         l in range(0,n-c-1):             df2.ix[l,c]=c_back(l,c,df)

i use 

for x in df.itertuples():

but don't know how modify specific cell value. thanks

use stack

for mytuple, value in df.stack().iteritems():     print(mytuple, value)

consider df

df = pd.dataframe(np.arange(9).reshape(-1, 3), list('abc'), list('xyz')) df

enter image description here

for mytuple, value in df.stack().iteritems():     print(mytuple, value)  ('a', 'x') 0 ('a', 'y') 1 ('a', 'z') 2 ('b', 'x') 3 ('b', 'y') 4 ('b', 'z') 5 ('c', 'x') 6 ('c', 'y') 7 ('c', 'z') 8

to set values of df

for (i, j), value in df.stack().iteritems():     df.set_value(i, j, value ** 2)  df

enter image description here


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