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Accessing class variables from a list comprehension in the class definition

... Class scope and list, set or dictionary comprehensions, as well as generator expressions do not mix. The why; or, the official word on this In Python 3, list comprehensions were given a proper scope (local namespace) of their own, to p...
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Factors in R: more than an annoyance?

... data types in R is factors. In my experience factors are basically a pain and I never use them. I always convert to characters. I feel oddly like I'm missing something. ...
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Why use the params keyword?

...ly doing to make the best choice. – Allen Clark Copeland Jr Nov 28 '15 at 22:15 2 ...
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Seedable JavaScript random number generator

The JavaScript Math.random() function returns a random value between 0 and 1, automatically seeded based on the current time (similar to Java I believe). However, I don't think there's any way to set you own seed for it. ...
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MySQL ON vs USING?

In a MySQL JOIN , what is the difference between ON and USING() ? As far as I can tell, USING() is just more convenient syntax, whereas ON allows a little more flexibility when the column names are not identical. However, that difference is so minor, you'd think they'd just do away with USI...
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How to add a progress bar to a shell script?

When scripting in bash or any other shell in *NIX, while running a command that will take more than a few seconds, a progress bar is needed. ...
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Binary search (bisection) in Python

Is there a library function that performs binary search on a list/tuple and return the position of the item if found and 'False' (-1, None, etc.) if not? ...
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Append an object to a list in R in amortized constant time, O(1)?

...oldlist, list(someobj)) In general, R types can make it hard to have one and just one idiom for all types and uses. share | improve this answer | follow | ...
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Pinging servers in Python

In Python, is there a way to ping a server through ICMP and return TRUE if the server responds, or FALSE if there is no response? ...
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Why do we need tuples in Python (or any immutable data type)?

I've read several python tutorials (Dive Into Python, for one), and the language reference on Python.org - I don't see why the language needs tuples. ...