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How can I create a Set of Sets in Python?
...m the following list of lists:
t = [[], [1, 2], [5], [1, 2, 5], [1, 2, 3, 4], [1, 2, 3, 6]]
you can create your set in the following way:
t1 = set(frozenset(i) for i in t)
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Turn off CSRF token in rails 3
...
Dorian
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answered Apr 14 '11 at 20:36
Mike LewisMike ...
Build vs new in Rails 3
...ion:
henrym:~/testapp$ rails c
Loading development environment (Rails 3.0.4)
r:001 > (some_firm = Firm.new).save # Create and save a new Firm
#=> true
r:002 > some_firm.clients # No clients yet
#=> []
r:003 > some_firm.clients.new # Create a new client
#=> #<C...
Grep regex NOT containing string
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beerbajaybeerbajay
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in_array multiple values
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answered Sep 24 '11 at 23:51
Mark ElliotMark Elliot
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filter items in a python dictionary where keys contain a specific string
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answered May 26 '14 at 3:49
Jonathon ReinhartJonathon Reinhart
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Summarizing multiple columns with dplyr? [duplicate]
... <dbl>
#> 1 1 3.08 2.98 2.98 2.91
#> 2 2 3.03 3.04 2.97 2.87
#> 3 3 2.85 2.95 2.95 3.06
If you want to summarize only certain columns, use summarise_at or summarise_if functions.
Alternatively, the purrrlyr package provides the same functionality:
library(purr...
Take the content of a list and append it to another list
... = range(2)
>>> b.append(a)
>>> b
[0, 1, 2, [0, 1, 2, 3, 4]]
>>> c.extend(a)
>>> c
[0, 1, 0, 1, 2, 3, 4]
Since list.extend() accepts an arbitrary iterable, you can also replace
for line in mylog:
list1.append(line)
by
list1.extend(mylog)
...
Pandas get topmost n records within each group
... value
id
1 0 1 1
1 1 2
2 3 2 1
4 2 2
3 7 3 1
4 8 4 1
(Keep in mind that you might need to order/sort before, depending on your data)
EDIT: As mentioned by the questioner, use df.groupby('id').head(2).reset_index(drop=True) to remo...