I am not able to clarify my self over the use of next()
in python(3).
I have a data :
chr pos ms01e_PI ms01e_PG_al ms02g_PI ms02g_PG_al ms03g_PI ms03g_PG_al ms04h_PI ms04h_PG_al
2 15881989 4 C|C 6 A|C 7 C|C 7 C|C
2 15882091 4 A|T 6 A|T 7 T|A 7 A|A
2 15882148 4 T|T 6 T|T 7 T|T 7 T|G
and I read it like:
Works fine
c = csv.DictReader(io.StringIO(data), dialect=csv.excel_tab)
print(c)
print(list(c))
Works fine
c = csv.DictReader(io.StringIO(data), dialect=csv.excel_tab)
print(c)
keys = next(c)
print('keys:', keys)
But, now there is a problem.
c = csv.DictReader(io.StringIO(data), dialect=csv.excel_tab)
print(c)
print(list(c))
keys = next(c)
print('keys:', keys)
Error message:
Traceback (most recent call last):
2 15882601 4 C|C 9 C|C 6 C|C 5 T|C
File "/home/everestial007/Test03.py", line 24, in <module>
keys = next(c)
File "/home/everestial007/anaconda3/lib/python3.5/csv.py", line 110, in __next__
row = next(self.reader)
StopIteration
Why does print(keys)
after print(list(c))
gives StopIteration
? I read the documentation but I am not clear on this particular example.
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