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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...
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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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pandas DataFrame: replace nan values with average of columns

... 283 You can simply use DataFrame.fillna to fill the nan's directly: In [27]: df Out[27]: ...
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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 ...
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How to use glob() to find files recursively?

...lib.Path.rglob from the the pathlib module, which was introduced in Python 3.5. from pathlib import Path for path in Path('src').rglob('*.c'): print(path.name) If you don't want to use pathlib, use can use glob.glob('**/*.c'), but don't forget to pass in the recursive keyword parameter and it ...
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What's the difference between VARCHAR and CHAR?

... 372 VARCHAR is variable-length. CHAR is fixed length. If your content is a fixed size, you'll ge...
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How do I loop through a list by twos? [duplicate]

... 392 You can use for in range with a step size of 2: Python 2 for i in xrange(0,10,2): print(i)...
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how to convert array values from string to int?

... | edited Apr 23 '19 at 10:46 Rahul 16.8k77 gold badges3434 silver badges5353 bronze badges a...
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Create Pandas DataFrame from a string

... 538 A simple way to do this is to use StringIO.StringIO (python2) or io.StringIO (python3) and pass...
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Group by multiple columns in dplyr, using string vector input

...e so: data = data.frame( asihckhdoydkhxiydfgfTgdsx = sample(LETTERS[1:3], 100, replace=TRUE), a30mvxigxkghc5cdsvxvyv0ja = sample(LETTERS[1:3], 100, replace=TRUE), value = rnorm(100) ) # get the columns we want to average within columns = names(data)[-3] library(dplyr) df1 <- data %...