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Append an object to a list in R in amortized constant time, O(1)?
...irthday. Some kind readers keep repeating any shortcomings with it, so by all means also see some of the comments below. One suggestion for list types:
newlist <- list(oldlist, list(someobj))
In general, R types can make it hard to have one and just one idiom for all types and uses.
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When should iteritems() be used instead of items()?
Is it legitimate to use items() instead of iteritems() in all places? Why was iteritems() removed from Python 3? Seems like a terrific and useful method. What's the reasoning behind it?
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Is there a decorator to simply cache function return values?
...maxsize=100, typed=False)
Decorator to wrap a function with a memoizing callable that saves up to the maxsize most recent calls. It can save time when an expensive or I/O bound function is periodically called with the same arguments.
Example of an LRU cache for computing Fibonacci numbers:
@lru...
Is it safe to push_back an element from the same vector?
If the second push_back causes a reallocation, the reference to the first integer in the vector will no longer be valid. So this isn't safe?
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Best practice for Python assert
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To be able to automatically throw an error when x become less than zero throughout the function. You can use class descriptors. Here is an example:
class LessThanZeroException(Exception):
pass
class variable(object):
def __init__(self, va...
What are good uses for Python3's “Function Annotations”
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I think this is actually great.
Coming from an academic background, I can tell you that annotations have proved themselves invaluable for enabling smart static analyzers for languages like Java. For instance, you could define semantics like sta...
javascript: Clear all timeouts?
Is there a way to clear all time outs from a given window? I suppose the timeouts are stored somewhere in the window object but couldn't confirm that.
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What Process is using all of my disk IO
If I use "top" I can see what CPU is busy and what process is using all of my CPU.
7 Answers
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String concatenation vs. string substitution in Python
...catenation is (significantly) faster according to my machine. But stylistically, I'm willing to pay the price of substitution if performance is not critical. Well, and if I need formatting, there's no need to even ask the question... there's no option but to use interpolation/templating.
>>&g...
What is an alternative to execfile in Python 3?
It seems they canceled in Python 3 all the easy way to quickly load a script by removing execfile()
12 Answers
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