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Changing Java Date one hour back
...ary of the fact that there is Calendar.HOUR which works with 12 hour clock and Calendar.HOUR_OF_DAY for 24 hour clock: chintat.blogspot.ca/2006/05/…
– Wolf
Apr 27 '15 at 17:24
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Determine the number of NA values in a column
...r of NA values in a data frame column. Say my data frame is called df , and the name of the column I am considering is col . The way I have come up with is following:
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Left Align Cells in UICollectionView
...ct a new line by inspecting the Y position of the new element. Very simple and quick in performance.
Swift:
class LeftAlignedCollectionViewFlowLayout: UICollectionViewFlowLayout {
override func layoutAttributesForElements(in rect: CGRect) -> [UICollectionViewLayoutAttributes]? {
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Can you break from a Groovy “each” closure?
...ndition.
Alternatively, you could use a "find" closure instead of an each and return true when you would have done a break.
This example will abort before processing the whole list:
def a = [1, 2, 3, 4, 5, 6, 7]
a.find {
if (it > 5) return true // break
println it // do the stuff th...
How to filter a dictionary according to an arbitrary condition function?
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Nowadays, in Python 2.7 and up, you can use a dict comprehension:
{k: v for k, v in points.iteritems() if v[0] < 5 and v[1] < 5}
And in Python 3:
{k: v for k, v in points.items() if v[0] < 5 and v[1] < 5}
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Linux equivalent of the Mac OS X “open” command [closed]
I've found the "open" command in Mac OS X very handy in the command line. From "man open":
7 Answers
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How can I print each command before executing? [duplicate]
What is the best way to set up a Bash script that prints each command before it executes it?
4 Answers
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How does tuple comparison work in Python?
I have been reading the Core Python programming book, and the author shows an example like:
4 Answers
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How to remove leading and trailing zeros in a string? Python
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What about a basic
your_string.strip("0")
to remove both trailing and leading zeros ? If you're only interested in removing trailing zeros, use .rstrip instead (and .lstrip for only the leading ones).
[More info in the doc.]
You could use some list comprehension to get the sequences you w...
How to normalize an array in NumPy?
...:
import numpy as np
from sklearn.preprocessing import normalize
x = np.random.rand(1000)*10
norm1 = x / np.linalg.norm(x)
norm2 = normalize(x[:,np.newaxis], axis=0).ravel()
print np.all(norm1 == norm2)
# True
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