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Python pandas Filtering out nan from a data selection of a column of strings
...NaN:
In [87]:
nms
Out[87]:
movie name rating
0 thg John 3
1 thg NaN 4
3 mol Graham NaN
4 lob NaN NaN
5 lob NaN NaN
[5 rows x 3 columns]
In [89]:
nms = nms.dropna(thresh=2)
In [90]:
nms[nms.name.notnull()]
Out[90]:
movie name rating
0...
Correct way to define C++ namespace methods in .cpp file
...se it shows that in the namespace, you are defining the function.
Version 3 is right also because you used the :: scope resolution operator to refer to the MyClass::method () in the namespace ns1. I prefer version 3.
See Namespaces (C++). This is the best way to do this.
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Is there an R function for finding the index of an element in a vector?
... function match works on vectors :
x <- sample(1:10)
x
# [1] 4 5 9 3 8 1 6 10 7 2
match(c(4,8),x)
# [1] 1 5
match only returns the first encounter of a match, as you requested. It returns the position in the second argument of the values in the first argument.
For multiple matching, ...
Check if two unordered lists are equal [duplicate]
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463
Python has a built-in datatype for an unordered collection of (hashable) things, called a set. I...
Constantly print Subprocess output while process is running
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13 Answers
13
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How to round to 2 decimals with Python?
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answered Dec 8 '13 at 18:20
roliszrolisz
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Remove ActiveRecord in Rails 3
Now that Rails 3 beta is out, I thought I'd have a look at rewriting an app I have just started work on in Rails 3 beta, both to get a feel for it and get a bit of a head-start. The app uses MongoDB and MongoMapper for all of its models and therefore has no need for ActiveRecord. In the previous ver...
Take the content of a list and append it to another list
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379
You probably want
list2.extend(list1)
instead of
list2.append(list1)
Here's the differen...
What does the slash mean in help() output?
What does the / mean in Python 3.4's help output for range before the closing parenthesis?
3 Answers
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Extract traceback info from an exception object
...to this question depends on the version of Python you're using.
In Python 3
It's simple: exceptions come equipped with a __traceback__ attribute that contains the traceback. This attribute is also writable, and can be conveniently set using the with_traceback method of exceptions:
raise Exceptio...