A
andrea crotti
So I was trying to use groupby (which I used in the past), but I
noticed a very strange thing if using list on
the result:
In [109]: s = sorted(s, key=keyfunc)
In [110]: s
Out[110]: [(1, 2), (1, 3), (1, 5), (2, 3)]
In [117]: m2 = list(groupby(s, keyfunc))
In [118]: for name, res in m2:
.....: for r in res:
.....: print name, r
.....:
2 (2, 3)
In [119]: m2 = groupby(s, keyfunc)
In [120]: for name, res in m2:
for r in res:
print name, r
.....:
1 (1, 2)
1 (1, 3)
1 (1, 5)
2 (2, 3)
How is that possible?
Generating the list first should be the same as iterating after, how
can it behave differently?
noticed a very strange thing if using list on
the result:
In [109]: s = sorted(s, key=keyfunc)
In [110]: s
Out[110]: [(1, 2), (1, 3), (1, 5), (2, 3)]
In [117]: m2 = list(groupby(s, keyfunc))
In [118]: for name, res in m2:
.....: for r in res:
.....: print name, r
.....:
2 (2, 3)
In [119]: m2 = groupby(s, keyfunc)
In [120]: for name, res in m2:
for r in res:
print name, r
.....:
1 (1, 2)
1 (1, 3)
1 (1, 5)
2 (2, 3)
How is that possible?
Generating the list first should be the same as iterating after, how
can it behave differently?