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Pandas - How to flatten a hierarchical index in columns
..., but leaves behind column names which are difficult to access programmatically and are not queriable
– dmeu
Jun 29 '17 at 8:53
1
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Error handling in Bash
...kens code's predictability and portability).
You can either let the trap call error for you (in which case it uses the default exit code of 1 and no message) or call it yourself and provide explicit values; for instance:
error ${LINENO} "the foobar failed" 2
will exit with status 2, and give an ...
How to get line count of a large file cheaply in Python?
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You can't get any better than that.
After all, any solution will have to read the entire file, figure out how many \n you have, and return that result.
Do you have a better way of doing that without reading the entire file? Not sure... The best solution will always ...
Why do we use __init__ in Python classes?
...Spot is a bit of a cripple and is mostly yellow. The __init__ function is called a constructor, or initializer, and is automatically called when you create a new instance of a class. Within that function, the newly created object is assigned to the parameter self. The notation self.legs is an attrib...
Replacing some characters in a string with another character
I have a string like AxxBCyyyDEFzzLMN and I want to replace all the occurrences of x , y , and z with _ .
5 Answers
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Getters \ setters for dummies
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Isnt it really painful that MS does not support JS correctly and they do not make their silverlight run everywhere, so I have to program everything twice, one for SL and one for rest of the world :)
– Akash Kava
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How do you get a query string on Flask?
...ut since this answer correctly answers the question my Google search terms alluded to ('flask get request parameter') I'm up-voting it anyhow. I'm a pedant too, but I'm chalking this up to web mysticism. ????
– Michael Scheper
Jan 13 '17 at 23:45
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multiprocessing.Pool: When to use apply, apply_async or map?
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Back in the old days of Python, to call a function with arbitrary arguments, you would use apply:
apply(f,args,kwargs)
apply still exists in Python2.7 though not in Python3, and is generally not used anymore. Nowadays,
f(*args,**kwargs)
is preferred. The...
How to find event listeners on a DOM node when debugging or from the JavaScript code?
...d A.com/js/jquery-ui-1.10.3.custom.js?_=1384831682813. Origin B.com is not allowed by Access-Control-Allow-Origin.
– hiway
Nov 19 '13 at 3:50
5
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How to implement a rule engine?
...Rules = rules.Select(r => CompileRule(r)).ToList();
public bool MatchesAllRules(User user)
{
return compiledRules.All(rule => rule(user));
}
Here is the implementation of BuildExpr:
Expression BuildExpr(Rule r, ParameterExpression param)
{
var left = MemberExpression.Property(param, ...