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List comprehension: Returning two (or more) items for each item
...: x ** 2
>>> list(chain.from_iterable((f(x), g(x)) for x in range(3)))
[2, 0, 3, 1, 4, 4]
Timings:
from timeit import timeit
f = lambda x: x + 2
g = lambda x: x ** 2
def fg(x):
yield f(x)
yield g(x)
print timeit(stmt='list(chain.from_iterable((f(x), g(x)) for x in range(3)))',...
Difference between float and decimal data type
...mysql> insert into numbers values (100, 100);
mysql> select @a := (a/3), @b := (b/3), @a * 3, @b * 3 from numbers \G
*************************** 1. row ***************************
@a := (a/3): 33.333333333
@b := (b/3): 33.333333333333
@a + @a + @a: 99.999999999000000000000000000000
@b + @b...
Cannot ping AWS EC2 instance
...
answered May 30 '15 at 9:39
RakibRakib
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How to install Hibernate Tools in Eclipse?
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13 Answers
13
Active
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Pandas percentage of total with groupby
...d
np.random.seed(0)
df = pd.DataFrame({'state': ['CA', 'WA', 'CO', 'AZ'] * 3,
'office_id': list(range(1, 7)) * 2,
'sales': [np.random.randint(100000, 999999)
for _ in range(12)]})
state_office = df.groupby(['state', 'office_id']).agg...
How can I disable logging of asset pipeline (sprockets) messages in Ruby on Rails 3.1?
... tends to be quite verbose in the (dev) log by default under Ruby on Rails 3.1 (RC1):
14 Answers
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Use find command but exclude files in two directories
...th ./scripts/
Testing the Solution:
$ mkdir a b c d e
$ touch a/1 b/2 c/3 d/4 e/5 e/a e/b
$ find . -type f ! -path "./a/*" ! -path "./b/*"
./d/4
./c/3
./e/a
./e/b
./e/5
You were pretty close, the -name option only considers the basename, where as -path considers the entire path =)
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Setting the selected value on a Django forms.ChoiceField
...alue when you instantiate the form:
form = MyForm(initial={'max_number': '3'})
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Cannot import XSSF in Apache POI
I am referencing the version 3.7 of the Apache POI and I am getting a "cannot be resolved" error when I do:
11 Answers
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What exactly does += do in python?
...r
return self.num
>>> a = Adder(2)
>>> a += 3
in __iadd__ 3
>>> a
5
Hope this helps.
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