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What is the fastest or most elegant way to compute a set difference using Javascript arrays?
...ty methods.)
Performance: Testing with
var a = [], b = [];
for (var i = 100000; i--; ) {
if (i % 2 !== 0) a.push(i);
if (i % 3 !== 0) b.push(i);
}
gives two sets with 50,000 and 66,666 elements. With these values A-B takes about 75ms, while union and intersection are
Inner text shadow with CSS
..."Multiple shadows? Don't even think." What about text-shadow: 1px 1px 1px #000, 3px 3px 5px blue;?
– Morpheus
Aug 2 '13 at 13:20
...
Best way to check if object exists in Entity Framework?
... your generic function IsExists<T>().
– Suncat2000
Nov 28 '18 at 21:48
...
#1071 - Specified key was too long; max key length is 767 bytes
...tation for InnoDB tables in MySQL version 5.6 (and prior versions). It's 1,000 bytes long for MyISAM tables. In MySQL version 5.7 and upwards this limit has been increased to 3072 bytes.
You also have to be aware that if you set an index on a big char or varchar field which is utf8mb4 encoded, you ...
Convert SVG to PNG in Python
...rosvg import svg2png
svg_code = """
<svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="#000" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
<circle cx="12" cy="12" r="10"/>
<line x1="12" y1="8" ...
How do I retrieve an HTML element's actual width and height?
...nd div all with the same css:
width:200px;
height:20px;
border:solid 1px #000;
padding:2px;
<input id="t" type="text" />
<input id="b" type="button" />
<div id="d"></div>
I tried it in chrome, firefox and ie-edge, I tried with jquery and without, and I tried it with and...
Best way to remove from NSMutableArray while iterating?
...sing 4 different methods. Each test iterated through all elements in a 100,000 element array, and removed every 5th item. The results did not vary much with/ without optimization. These were done on an iPad 4:
(1) removeObjectAtIndex: -- 271 ms
(2) removeObjectsAtIndexes: -- 1010 ms (because build...
How to sum a variable by group
... will be quite a lot faster than base functions, however (can well be 100-1000 times faster for some operations). Also see here
– talat
Jan 23 '15 at 14:50
...
What's the best way to set a single pixel in an HTML5 canvas?
...ower than the other methods. This may be true if your plotting less than 1000, but from there onwards this method starts winning and then slaughtering the other methods. Here's a test case.... measurethat.net/Benchmarks/Show/8386/0/…
– PAEz
May 27 at 2:11
...
Convert one date format into another in PHP
...m-d H:i:s');
If the timestamp you have is in milliseconds (it may end in 000 and/or the timestamp is thirteen characters long) you will need to convert it to seconds before you can can convert it to another format. There's two ways to do this:
Trim the last three digits off using substr()
Trim...