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Can an html element have multiple ids?
...answered Apr 16 '11 at 7:53
user123444555621user123444555621
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...
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...
Checking if a string can be converted to float in Python
... ------------
print(isfloat("")) False
print(isfloat("1234567")) True
print(isfloat("NaN")) True nan is also float
print(isfloat("NaNananana BATMAN")) False
print(isfloat("123.456")) True
print(isfloat("123.E4")) ...
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
...
What does -> mean in Python function definitions?
...versions.
According to this, the example you've supplied:
def f(x) -> 123:
return x
will be forbidden in the future (and in current versions will be confusing), it would need to be changed to:
def f(x) -> int:
return x
for it to effectively describe that function f returns an ob...
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...
What does the “yield” keyword do?
...one, etc. And generators return... well that's where yield comes in:
def f123():
yield 1
yield 2
yield 3
for item in f123():
print item
Instead of yield statements, if you had three return statements in f123() only the first would get executed, and the function would exit. But f1...
What data type to use for money in Java? [closed]
...yAmount = amountFactory.setCurrency(Monetary.getCurrency("EUR")).setNumber(12345.67).create();
MonetaryAmountFormat format = MonetaryFormats.getAmountFormat(Locale.getDefault());
System.out.println(format.format(monetaryAmount));
When using the reference implementation API, the necessary code is m...
Easiest way to convert int to string in C++
...
@Rasoul NumberToString(23213.123) produces 23213.1 while std::to_string(23213.123) produces 23213.123000 What happens there?
– Killzone Kid
Nov 5 '17 at 23:00
...
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...