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“Large data” work flows using pandas
... one contains different fields, or do they have some records per file with all of the fields in each file?
Do you ever select subsets of rows (records) based on criteria (e.g. select the rows with field A > 5)? and then do something, or do you just select fields A, B, C with all of the records (a...
In a django model custom save() method, how should you identify a new object?
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Not all models have an id attribute, i.e. a model extending another through a models.OneToOneField(OtherModel, primary_key=True). I think you need to use self.pk
– AJP
Apr 9 '13 at 10:21
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Javascript/DOM: How to remove all events of a DOM object?
Just question: Is there any way to completely remove all events of an object, e.g. a div?
12 Answers
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What is the best way to implement nested dictionaries?
I have a data structure which essentially amounts to a nested dictionary. Let's say it looks like this:
21 Answers
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How do you programmatically set an attribute?
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Damn shame it doesn't work in all cases, as that would be really useful, for example, for adding the dirty attribute to user input...
– brice
Feb 28 '12 at 18:32
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What is the preferred/idiomatic way to insert into a map?
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First of all, operator[] and insert member functions are not functionally equivalent :
The operator[] will search for the key, insert a default constructed value if not found, and return a reference to which you assign a value. Obvi...
How do I capture SIGINT in Python?
...f KeyboardInterruptException is implemented as a SIGINT handler or if it really only catches Ctrl+C presses, but either way, using a signal handler makes your intent explicit (at least, if your intent is the same as OP's). More importantly though, with a signal you don't have to wrap try-catches ar...
Finding the index of an item in a list
... complete. Some caveats about list.index follow. It is probably worth initially taking a look at the documentation for it:
list.index(x[, start[, end]])
Return zero-based index in the list of the first item whose value is equal to x. Raises a ValueError if there is no such item.
The optional argum...
Should import statements always be at the top of a module?
...t that's only paid once.
Putting the imports within a function will cause calls to that function to take longer.
So if you care about efficiency, put the imports at the top. Only move them into a function if your profiling shows that would help (you did profile to see where best to improve perform...
How to make MySQL handle UTF-8 properly
... My understanding is that utf8 within MySQL only refers to a small subset of full Unicode. You should use utf8mb4 instead to force full support. See mathiasbynens.be/notes/mysql-utf8mb4 "For a long time, I was using MySQL’s utf8 charset for databases, tables, and columns, assuming i...