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numpy: most efficient frequency counts for unique values in an array
...y 1.9, the easiest and fastest method is to simply use numpy.unique, which now has a return_counts keyword argument:
import numpy as np
x = np.array([1,1,1,2,2,2,5,25,1,1])
unique, counts = np.unique(x, return_counts=True)
print np.asarray((unique, counts)).T
Which gives:
[[ 1 5]
[ 2 3]
...
Why does NULL = NULL evaluate to false in SQL server
...
Think of the null as "unknown" in that case (or "does not exist"). In either of those cases, you can't say that they are equal, because you don't know the value of either of them. So, null=null evaluates to not true (false or null, depending on you...
iPad keyboard will not dismiss if modal ViewController presentation style is UIModalPresentationForm
...eem to be a way to work around it.
UPDATE:
In iOS 4.3 and later, you can now implement `-disablesAutomaticKeyboardDismissal' on your view controller to return NO:
- (BOOL)disablesAutomaticKeyboardDismissal {
return NO;
}
This fixes the issue.
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Should I use px or rem value units in my CSS? [closed]
...
TL;DR: use px.
The Facts
First, it's extremely important to know that per spec, the CSS px unit does not equal one physical display pixel. This has always been true – even in the 1996 CSS 1 spec.
CSS defines the reference pixel, which measures the size of a pixel on a 96 dpi displa...
Swift double to string
...fore I updated xCode 6, I had no problems casting a double to a string but now it gives me an error
14 Answers
...
use Winmerge inside of Git to file diff
...mple git config diff.tool winmerge will be enough.
Git 2.5+ (Q2, 2015) is now aware of Winmerge as a diff or merge tool!
Original answer (2009-2012)
(msysgit, 1.6.5, DOS session)
The first part (using winmerge) is described in "How do I view ‘git diff’ output with visual diff program?"
C:...
Why shouldn't I use mysql_* functions in PHP?
...jan Marjanovic will help you to choose.
And a better way is PDO, and I am now writing a simple PDO tutorial.
A simple and short PDO tutorial
Q. First question in my mind was: what is `PDO`?
A. “PDO – PHP Data Objects – is a database access layer providing a uniform method of access to ...
When using Spring Security, what is the proper way to obtain current username (i.e. SecurityContext)
I have a Spring MVC web app which uses Spring Security. I want to know the username of the currently logged in user. I'm using the code snippet given below . Is this the accepted way?
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Are JavaScript strings immutable? Do I need a “string builder” in JavaScript?
...135 | 1135 | 1200 | 4357 | 1137 | 1188 | 4294 |
Findings
Nowadays, all evergreen browsers handle string concatenation well. Array.join only helps IE 11
Overall, Opera is fastest, 4 times as fast as Array.join
Firefox is second and Array.join is only slightly slower in FF but consi...
How to detect orientation change?
...on while using the camera with AVFoundation, and found that the didRotate (now deprecated) & willTransition methods were unreliable for my needs. Using the notification posted by David did work, but is not current for Swift 3.x/4.x.
Swift 4.2
The notification name has been changed.
The closure...