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List of lists changes reflected across sublists unexpectedly
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When you write [x]*3 you get, essentially, the list [x, x, x]. That is, a list with 3 references to the same x. When you then modify this single x it is visible via all three references to it:
x = [1] * 4
l = [x] * 3
print(f"id(x): {id(x)}")
# id(x): 1405608979...
Generate a heatmap in MatPlotLib using a scatter data set
...50 heatmap. If you want, say, 512x384, you can put bins=(512, 384) in the call to histogram2d.
Example:
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Get notified when UITableView has finished asking for data?
...eload its data. So, when the second NSLog is fired, the table view has actually finish asking for data.
I've subclassed UITableView to send methods to the delegate before and after reloadData. It works like a charm.
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How to disable Crashlytics during development
...orting from the Crashlytics web dashboard for the debug version.
Wrap the call to Crashlytics.start() in an if statement that checks a debug flag. You could use either a custom flag or an approach like the ones proposed here: How to check if APK is signed or "debug build"?
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How can I change an element's class with JavaScript?
...r, going into detail on this is beyond the scope of the answer.
To change all classes for an element:
To replace all existing classes with one or more new classes, set the className attribute:
document.getElementById("MyElement").className = "MyClass";
(You can use a space-delimited list to app...
Run php script as daemon process
...tions need to be taken as soon as instruction arrives. I know PHP is not really the best option for daemon processes due to memory management issues, but due to various reasons I have to use PHP in this case. I came across a tool by libslack called Daemon ( http://libslack.org/daemon ) it seems to h...
float:left; vs display:inline; vs display:inline-block; vs display:table-cell;
... that now though. But the important thing is it does work, and it works in all browsers (even IE6/7), so use it if you like it.
The additional markup for clearing may not be necessary if you use the :after selector to clear the floats, but this isn't an option if you want to support IE6 or IE7.
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Get real path from URI, Android KitKat new storage access framework [duplicate]
Before the new gallery access in Android 4.4 (KitKat) I got my real path on the SD card with this method:
9 Answers
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How can I use numpy.correlate to do autocorrelation?
...olution, C(t)=∑ -∞ < i < ∞ aivt+i where -∞ < t < ∞, allows for results from -∞ to ∞, but you obviously can't store an infinitely long array. So it has to be clipped, and that is where the mode comes in. There are 3 different modes: full, same, & valid:
"full" mode r...
Why does !{}[true] evaluate to true in JavaScript?
...undefined) must therefore be defined. If something is defined then it's usually interpreted as true.
– OozeMeister
Oct 31 '13 at 16:50
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