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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(....
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...
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
...
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]:
...
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 ...
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 ...
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...
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)...
how to convert array values from string to int?
...
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edited Apr 23 '19 at 10:46
Rahul
16.8k77 gold badges3434 silver badges5353 bronze badges
a...
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...