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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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How to round to 2 decimals with Python?
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answered Dec 8 '13 at 18:20
roliszrolisz
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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...
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...
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...
Convert column classes in data.table
...rter)]
str(dtnew)
Classes ‘data.table’ and 'data.frame': 10 obs. of 3 variables:
$ ID : Factor w/ 2 levels "A","B": 1 1 1 1 1 2 2 2 2 2
$ Quarter: chr "1" "2" "3" "4" ...
$ value : num -0.838 0.146 -1.059 -1.197 0.282 ...
Using lapply and as.character:
dtnew <- dt[, lapply(....
Delete files older than 3 months old in a directory using .NET
...o know (using C#) how I can delete files in a certain directory older than 3 months, but I guess the date period could be flexible.
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Numpy argsort - what is it doing?
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Returns the indices that would sort an array.
2 is the index of 0.0.
3 is the index of 0.1.
1 is the index of 1.41.
0 is the index of 1.48.
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How to find out what type of a Mat object is with Mat::type() in OpenCV
...e CV_16U: r = "16U"; break;
case CV_16S: r = "16S"; break;
case CV_32S: r = "32S"; break;
case CV_32F: r = "32F"; break;
case CV_64F: r = "64F"; break;
default: r = "User"; break;
}
r += "C";
r += (chans+'0');
return r;
}
If M is a var of type Mat you can call it ...
pandas DataFrame: replace nan values with average of columns
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283
You can simply use DataFrame.fillna to fill the nan's directly:
In [27]: df
Out[27]:
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