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Combine two columns of text in pandas dataframe
I have a 20 x 4000 dataframe in Python using pandas. Two of these columns are named Year and quarter . I'd like to create a variable called period that makes Year = 2000 and quarter= q2 into 2000q2 .
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How does Java handle integer underflows and overflows and how would you check for it?
...tic boolean willAdditionOverflow(int left, int right) {
if (right < 0 && right != Integer.MIN_VALUE) {
return willSubtractionOverflow(left, -right);
} else {
return (~(left ^ right) & (left ^ (left + right))) < 0;
}
}
public static boolean willSubtracti...
Why #define TRUE (1==1) in a C boolean macro instead of simply as 1?
...) and actually use true and false.
In a C compiler, this is equivalent to 0 and 1.
(note that removing the parentheses will break that due to order of operations)
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Accessing items in an collections.OrderedDict by index
...> d.items()
[('foo', 'python'), ('bar', 'spam')]
>>> d.items()[0]
('foo', 'python')
>>> d.items()[1]
('bar', 'spam')
Note for Python 3.X
dict.items would return an iterable dict view object rather than a list. We need to wrap the call onto a list in order to make the indexing...
Get loop count inside a Python FOR loop
...
605
The pythonic way is to use enumerate:
for idx,item in enumerate(list):
...
What does glLoadIdentity() do in OpenGL?
...lent of 1, is not exactly correct. The matrix actually looks like this:
1 0 0 0
0 1 0 0
0 0 1 0
0 0 0 1
That is the identity matrix. Boon is correct, mathematically, that any matrix multiplied with that matrix (or a matrix that looks like that; diagonal ones, all else 0s) will result in the origi...
How can I detect if the user is on localhost in PHP?
...ient requesting is given by the web server.
$whitelist = array(
'127.0.0.1',
'::1'
);
if(!in_array($_SERVER['REMOTE_ADDR'], $whitelist)){
// not valid
}
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How to get different colored lines for different plots in a single figure?
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E.g.:
import matplotlib.pyplot as plt
import numpy as np
x = np.arange(10)
plt.plot(x, x)
plt.plot(x, 2 * x)
plt.plot(x, 3 * x)
plt.plot(x, 4 * x)
plt.show()
And, as you may already know, you can easily add a legend:
import matplotlib.pyplot as plt
import numpy as np
x = np.arange(10)
plt...
How might I convert a double to the nearest integer value?
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answered Mar 11 '09 at 4:33
nickfnickf
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Replace all elements of Python NumPy Array that are greater than some value
...o replace all values in it greater than or equal to a threshold T with 255.0. To my knowledge, the most fundamental way would be:
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