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What are POD types in C++?
...ointer-to-member type.
Greater detail can be found in this answer for C++98/03. C++11 changed the rules surrounding POD, relaxing them greatly, thus necessitating a follow-up answer here.
share
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ElasticSearch, Sphinx, Lucene, Solr, Xapian. Which fits for which usage? [closed]
...t;";
exit("done");
?>
Sample result:
[array] =>
"id" => 123,
"title" => "My post title.",
"content" => "My <p>post</p> content.",
...
[ and other fields ]
Sphinx query time:
0.001 sec.
Sphinx query time (1k concurrent):
=> 0.346 sec. (average)
...
Compiling C++11 with g++
...age:
The compiler can accept several base standards, such as c89 or c++98,
and GNU dialects of those standards, such as gnu89 or gnu++98. By
specifying a base standard, the compiler will accept all programs
following that standard and those using GNU extensions that do not
contradict it....
How to remove unused imports from Eclipse
...swered Mar 26 '13 at 6:24
niknik123niknik123
18111 silver badge77 bronze badges
...
How to use cURL to get jSON data and decode the data?
...wer your question :P
$url="https://.../api.php?action=getThreads&hash=123fajwersa&node_id=4&order_by=post_date&order=desc&limit=1&grab_content&content_limit=1";
Using cURL
// Initiate curl
$ch = curl_init();
// Will return the response, if false it print the re...
C# short/long/int literal format?
...by F or f is of type float. For example, the literals 1f, 1.5f, 1e10f, and 123.456F are all of type float.
A real literal suffixed by D or d is of type double. For example, the literals 1d, 1.5d, 1e10d, and 123.456D are all of type double.
A real literal suffixed by M or m is of type decimal. For ex...
jQuery Scroll To bottom of the page
... answered Jul 10 '15 at 13:35
f123f123
36422 silver badges88 bronze badges
...
SQL query for finding records where count > 1
...p int(11) not null,
dt date not null
);
insert into payment values
(1,123,55555,'2009-12-12'),
(1,123,66666,'2009-12-12'),
(1,123,77777,'2009-12-13'),
(2,456,77777,'2009-12-14'),
(2,456,77777,'2009-12-14'),
(2,789,77777,'2009-12-14'),
(2,789,77777,'2009-12-14');
select foo.user_id, foo.cnt fro...
sed: print only matching group
...it with a 2nd grep.
# To extract \1 from /xx([0-9]+)yy/
$ echo "aa678bb xx123yy xx4yy aa42 aa9bb" | grep -Eo 'xx[0-9]+yy' | grep -Eo '[0-9]+'
123
4
# To extract \1 from /a([0-9]+)b/
$ echo "aa678bb xx123yy xx4yy aa42 aa9bb" | grep -Eo 'a[0-9]+b' | grep -Eo '[0-9]+'
678
9
...
Remove duplicated rows using dplyr
...ction for this purpose.
Original answer below:
library(dplyr)
set.seed(123)
df <- data.frame(
x = sample(0:1, 10, replace = T),
y = sample(0:1, 10, replace = T),
z = 1:10
)
One approach would be to group, and then only keep the first row:
df %>% group_by(x, y) %>% filter(row_nu...