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Accessing dict_keys element by index in Python3
... 'world'}
>>> list(test)
['foo', 'hello']
>>> list(test)[0]
'foo'
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getViewTypeCount and getItemViewType methods of ArrayAdapter
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308
These handle the case where you want different types of view for different rows. For instance, ...
Google Map API v3 — set bounds and center
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answered Feb 5 '10 at 7:14
spencercoolyspencercooly
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how do you filter pandas dataframes by multiple columns
...sub-statements with ():
males = df[(df[Gender]=='Male') & (df[Year]==2014)]
To store your dataframes in a dict using a for loop:
from collections import defaultdict
dic={}
for g in ['male', 'female']:
dic[g]=defaultdict(dict)
for y in [2013, 2014]:
dic[g][y]=df[(df[Gender]==g) & ...
Sass and combined child selector
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edited Apr 30 '15 at 22:58
Continuity8
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Boolean.hashCode()
...?
Suppose for a second that we picked composite numbers (non-primes), say 1000 and 2000. When inserting booleans into a hash table, true and false would go into bucket 1000 % N resp 2000 % N (where N is the number of buckets).
Now notice that
1000 % 8 same bucket as 2000 % 8
1000 % 10 same buck...
iOS: Compare two dates
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210
According to Apple documentation of NSDate compare:
Returns an NSComparisonResult value that...
Pass a data.frame column name to a function
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109
You can just use the column name directly:
df <- data.frame(A=1:10, B=2:11, C=3:12)
fun1 &l...
Python - abs vs fabs
...pe of its argument.
In [7]: type(abs(-2))
Out[7]: int
In [8]: type(abs(-2.0))
Out[8]: float
In [9]: type(abs(3+4j))
Out[9]: float
In [10]: type(math.fabs(-2))
Out[10]: float
In [11]: type(math.fabs(-2.0))
Out[11]: float
In [12]: type(math.fabs(3+4j))
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How exactly does a generator comprehension work?
... # notice it's a generator object
<generator object <genexpr> at 0x7f2ad75f89e0>
>>> len(filtered_gen) # So technically, it has no length
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: object of type 'generator' has no len()
>...