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How can I use “.” as the delimiter with String.split() in java [duplicate]
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203
String.split takes a regex, and '.' has a special meaning for regexes.
You (probably) want some...
Downloading a picture via urllib and python
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263
Python 2
Using urllib.urlretrieve
import urllib
urllib.urlretrieve("http://www.gunnerkrigg.com...
How to sort Counter by value? - python
...;> from collections import Counter
>>> x = Counter({'a':5, 'b':3, 'c':7})
>>> x.most_common()
[('c', 7), ('a', 5), ('b', 3)]
It'll do so in the most efficient manner possible; if you ask for a Top N instead of all values, a heapq is used instead of a straight sort:
>>&g...
How do I profile memory usage in Python?
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123
This one has been answered already here: Python memory profiler
Basically you do something like...
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...
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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Cannot ping AWS EC2 instance
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answered May 30 '15 at 9:39
RakibRakib
8,9821010 gold badges5555 silver badges9090 bronze badges
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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...