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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...
Oracle “(+)” Operator
..."adding NULL values if no match found". For example, "a.id=b.id(+)" means allow b.id to be NULL if there is no match with a.id.
– beach
Oct 26 '10 at 5:00
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To underscore or to not to underscore, that is the question
...other framework languages? For example since C# is case-sensitive you can call a field "foo" and the public property "Foo" and it works fine.
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How to access outer class from an inner class?
...d Jan 7 '10 at 23:54
Daniel VassalloDaniel Vassallo
301k6666 gold badges475475 silver badges424424 bronze badges
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How to change the name of a Django app?
...e changed the name of an app in Django by renaming its folder, imports and all its references (templates/indexes). But now I get this error when I try to run python manage.py runserver
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TypeError: got multiple values for argument
...r and it seems that my problem has an interesting distinct difference than all the posts I read so far, namely, all the other posts so far have the error in regards to either a user created class or a builtin system resource. I am experiencing this problem when calling a function, I can't figure out...
What is the best way to compute trending topics or tags?
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This problem calls for a z-score or standard score, which will take into account the historical average, as other people have mention, but also the standard deviation of this historical data, making it more robust than just using the avera...
AttributeError: 'datetime' module has no attribute 'strptime'
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What's the bad magic number error?
...the pyc file or trying to run a pyc from a different version of python (usually later) than your interpreter.
If they are your pyc files, just delete them and let the interpreter re-compile the py files. On UNIX type systems, that could be something as simple as:
rm *.pyc
or:
find . -name '*.py...
What is the difference between a mutable and immutable string in C#?
...pe
To "effect a change" on a string represented as a C# String, you actually create a new String object. The original String is not changed ... because it is unchangeable.
In most cases it is better to use String because it is easier reason about them; e.g. you don't need to consider the possib...