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Getting a list of associative array keys
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I'm switching this to the accepted answer now. Only IE8 doesn't support it anymore (for which a polyfill is available developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/…)
– Simon_Weaver
Dec 11 '17 at 1:55
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Why does the 260 character path length limit exist in Windows?
...used here for visual clarity and cannot be part of a valid path string.)
Now we see that it is 1+2+256+1 or [drive][:\][path][null] = 260. One could assume that 256 is a reasonable fixed string length from the DOS days. And going back to the DOS APIs we realize that the system tracked the current ...
Why is iterating through a large Django QuerySet consuming massive amounts of memory?
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Small improvements now possible since post. Paginator now has a page_range property to avoid boilerplate. If in search of minimal memory overhead, you can use object_list.iterator() which will not populate the queryset cache. prefetch_relat...
File to byte[] in Java
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This now works on Android if targeting SDK version 26 and higher.
– JamesNWarner
Aug 9 '17 at 14:46
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How to get TimeZone from android mobile?
...for getting currect time zone :
TimeZone tz = TimeZone.getDefault();
Date now = new Date();
//Import part : x.0 for double number
double offsetFromUtc = tz.getOffset(now.getTime()) / 3600000.0;
String m2tTimeZoneIs = Double.parseDouble(offsetFromUtc);
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Null vs. False vs. 0 in PHP
...s.
0 is an int. Nothing to do with the rest above, used for mathematics.
Now, what is tricky, it's that in dynamic languages like PHP, all of them have a value in a boolean context, which (in PHP) is False.
If you test it with ==, it's testing the boolean value, so you will get equality. If you t...
Difference between classification and clustering in data mining? [closed]
...neral, in classification you have a set of predefined classes and want to know which class a new object belongs to.
Clustering tries to group a set of objects and find whether there is some relationship between the objects.
In the context of machine learning, classification is supervised learning ...
Can JavaScript connect with MySQL?
...e if such libraries exist, but they are possible.
EDIT: Since writing, we now have MySQL Cluster:
The MySQL Cluster JavaScript Driver for Node.js is just what it sounds like it is – it’s a connector that can be called directly from your JavaScript code to read and write your data. As it acc...
NPM doesn't install module dependencies
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@Flame2057 it's good to know you're out of luck, though not too informative. You may go ahead and formulate a question, hopefully the community has the knowledge to solve. Have fun!
– allprog
Jul 17 '17 at 14:17...
HTML encoding issues - “” character showing up instead of “ ”
...he HTML itself, which is always a highly dodgy business.
Well anyway, for now you can add one of the following to your document's <head> and see if that makes it look right in the browser:
for HTML4: <meta http-equiv="Content-Type" content="text/html;charset=utf-8" />
for HTML5: <m...