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Set value for particular cell in pandas DataFrame using index
...y df.
In [18]: %timeit df.set_value('C', 'x', 10)
100000 loops, best of 3: 2.9 µs per loop
In [20]: %timeit df['x']['C'] = 10
100000 loops, best of 3: 6.31 µs per loop
In [81]: %timeit df.at['C', 'x'] = 10
100000 loops, best of 3: 9.2 µs per loop
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Java: Get first item from a collection
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131
Iterables.get(yourC, indexYouWant)
Because really, if you're using Collections, you should be ...
Running shell command and capturing the output
...ons, it is no longer the recommended approach.
Modern versions of Python (3.5 or higher): run
If you're using Python 3.5 or higher, and do not need backwards compatibility, the new run function is recommended. It provides a very general, high-level API for the subprocess module. To capture the out...
`staticmethod` and `abc.abstractmethod`: Will it blend?
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35
class abstractstatic(staticmethod):
__slots__ = ()
def __init__(self, function):
...
Why is semicolon allowed in this python snippet?
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233
Python does not require semi-colons to terminate statements. Semi colons can be used to delimi...
vim deleting backward tricks
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answered Sep 3 '09 at 15:01
Lucas OmanLucas Oman
14.4k22 gold badges4242 silver badges4545 bronze badges
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ValueError: The truth value of an array with more than one element is ambiguous. Use a.any() or a.al
...wo arrays to be evaluated in boolean context (by
calling __bool__ in Python3 or __nonzero__ in Python2).
Your original code
mask = ((r["dt"] >= startdate) & (r["dt"] <= enddate))
selected = r[mask]
looks correct. However, if you do want and, then instead of a and b use (a-b).any() or ...
Transform DateTime into simple Date in Ruby on Rails
...paging, ignore! :-)
– Notinlist
Sep 3 '10 at 8:56
@Notinlist the entirety of rails is written in Ruby, so you could pr...
Xcode doesn't show the line that causes a crash
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301
You should also ensure that you have breakpoints set for all exceptions. This will cause Xcod...
What's with 181783497276652981 and 8682522807148012 in Random (Java 7)?
Why were 181783497276652981 and 8682522807148012 chosen in Random.java ?
3 Answers
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