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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")) ...
How to find corresponding log files folder for a web site?
There are multiple web sites and multiple folders under inetpub\logs\LogFiles (W3SVC1, W3SVC2, etc). How can I find what folder is used by a given web site?
...
Dynamic SQL - EXEC(@SQL) versus EXEC SP_EXECUTESQL(@SQL)
...
EXEC('SELECT * FROM FOO WHERE ID=?', 123) will replace the parameter placeholder "?" with the value 123 and then execute the query, returning a result for SELECT * FROM FOO WHERE ID=123
– Peter Wone
Jun 1 '10 at 23:27
...
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 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...
Nginx not picking up site in sites-enabled?
... figured out why this doesn't work! I am trying to move my localhost to my sites-enabled folder which is in /etc/nginx/sites-enabled/default.
...
nginx missing sites-available directory
...osts. The problem I am having is that I can't seem to find the /etc/nginx/sites-available directory.
3 Answers
...
module.exports vs exports in Node.js
...:
var x = require('file1.js');
contents of file1.js:
module.exports = '123';
When the above statement is executed, a Module object is created. Its constructor function is:
function Module(id, parent) {
this.id = id;
this.exports = {};
this.parent = parent;
if (parent &&...
CSS \9 in width property
... \0 instead of \9 will apply it to IE10 as well
– abc123
Oct 9 '13 at 21:26
21
@abc123 lets hope ...