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numpy: most efficient frequency counts for unique values in an array
...x = np.array([1,1,1,2,2,2,5,25,1,1])
y = np.bincount(x)
ii = np.nonzero(y)[0]
And then:
zip(ii,y[ii])
# [(1, 5), (2, 3), (5, 1), (25, 1)]
or:
np.vstack((ii,y[ii])).T
# array([[ 1, 5],
[ 2, 3],
[ 5, 1],
[25, 1]])
or however you want to combine the counts and th...
Check if a string has white space
...e input string:
function hasWhiteSpace(s) {
return s.indexOf(' ') >= 0;
}
Or you can use the test method, on a simple RegEx:
function hasWhiteSpace(s) {
return /\s/g.test(s);
}
This will also check for other white space characters like Tab.
...
'IF' in 'SELECT' statement - choose output value based on column values
...
1039
SELECT id,
IF(type = 'P', amount, amount * -1) as amount
FROM report
See http://dev....
Is there a TRY CATCH command in Bash
... |
edited Feb 19 at 5:20
answered Feb 25 '14 at 9:50
Jay...
How to display long messages in logcat
... to display long message on logcat. If the length of message is more than 1000 characters, it gets broken.
10 Answers
...
What is the max size of localStorage values?
...ly as an improvement on cookies, providing much greater storage capacity (10 MB per origin in Google Chrome(https://plus.google.com/u/0/+FrancoisBeaufort/posts/S5Q9HqDB8bh), Mozilla Firefox, and Opera; 10 MB per storage area in Internet Explorer) and better programmatic interfaces.
And also quotin...
A Windows equivalent of the Unix tail command [closed]
...
answered Oct 9 '08 at 14:50
Ryan DuffieldRyan Duffield
15.9k66 gold badges3636 silver badges3838 bronze badges
...
How to “warm-up” Entity Framework? When does it get “cold”?
...
+100
What would be the best approach to have high availability on my Entity Framework at anytime?
You can go for a mix of pregenerated ...
What is the purpose of setting a key in data.table?
...e other vignettes that we plan to.
I've updated this answer again (Feb 2016) in light of the new on= feature that allows ad-hoc joins as well. See history for earlier (outdated) answers.
What exactly does setkey(DT, a, b) do?
It does two things:
reorders the rows of the data.table DT by the...
How do negative margins in CSS work and why is (margin-top:-5 != margin-bottom:5)?
...e element, so why do you have to set margin-top:-8px; and not margin-top:-50%;?
Well, vertical centering in CSS is harder than it should be. When setting even top or bottom margins in %, the value is calculated as a percentage always relative to the width of the containing block. This is rather a c...