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What is RSS and VSZ in Linux memory management
...ot used, and memory that is from shared libraries.
So if process A has a 500K binary and is linked to 2500K of shared libraries, has 200K of stack/heap allocations of which 100K is actually in memory (rest is swapped or unused), and it has only actually loaded 1000K of the shared libraries and 400K...
Sass negative variable value?
...
Try it like this
margin: 0 (-$pad) 20px (-$pad);
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Count with IF condition in MySQL query
...ELECT
ccc_news . * ,
SUM(if(ccc_news_comments.id = 'approved', 1, 0)) AS comments
FROM
ccc_news
LEFT JOIN
ccc_news_comments
ON
ccc_news_comments.news_id = ccc_news.news_id
WHERE
`ccc_news`.`category` = 'news_layer2'
AND `ccc_news`.`status` = 'Active'
GROU...
Why does the month argument range from 0 to 11 in JavaScript's Date constructor?
...
60
It's an old (probably unfortunate, probably dying) tradition in the programming world, see the o...
Round to at most 2 decimal places (only if necessary)
...
Use Math.round(num * 100) / 100
Edit: to ensure things like 1.005 round correctly, we use
Math.round((num + Number.EPSILON) * 100) / 100
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Extract a regular expression match
...nd adds a few that are missing:
library(stringr)
str_locate("aaa12xxx", "[0-9]+")
# start end
# [1,] 4 5
str_extract("aaa12xxx", "[0-9]+")
# [1] "12"
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What does the tilde (~) mean in my composer.json file?
... means next significant release. In your case, it is equivalent to >= 2.0, < 3.0.
The full explanation is at Tilde Version Range docs page:
The ~ operator is best explained by example: ~1.2 is equivalent to >=1.2 <2.0.0, while ~1.2.3 is equivalent to >=1.2.3 <1.3.0.
Anoth...
.toArray(new MyClass[0]) or .toArray(new MyClass[myList.size()])?
...est version, on Hotspot 8, is:
MyClass[] arr = myList.toArray(new MyClass[0]);
I have run a micro benchmark using jmh the results and code are below, showing that the version with an empty array consistently outperforms the version with a presized array. Note that if you can reuse an existing arr...
Convert a byte array to integer in Java and vice versa
...rticular, the ByteBuffer. It can do all the work for you.
byte[] arr = { 0x00, 0x01 };
ByteBuffer wrapped = ByteBuffer.wrap(arr); // big-endian by default
short num = wrapped.getShort(); // 1
ByteBuffer dbuf = ByteBuffer.allocate(2);
dbuf.putShort(num);
byte[] bytes = dbuf.array(); // { 0, 1 }
...
Python list iterator behavior and next(iterator)
...tion to i being printed each iteration:
>>> a = iter(list(range(10)))
>>> for i in a:
... print(i)
... next(a)
...
0
1
2
3
4
5
6
7
8
9
So 0 is the output of print(i), 1 the return value from next(), echoed by the interactive interpreter, etc. There are just 5 iterations, ...