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Select multiple columns in data.table by their numeric indices
...
For versions of data.table >= 1.9.8, the following all just work:
library(data.table)
dt <- data.table(a = 1, b = 2, c = 3)
# select single column by index
dt[, 2]
# b
# 1: 2
# select multiple columns by index
dt[, 2:3]
# b c
# 1: 2 3
# select single column by na...
How to have stored properties in Swift, the same way I had on Objective-C?
...n't work : static var means that the value of the property is the same for all instance
– Fry
Mar 8 '17 at 15:40
@fry ...
Running multiple TeamCity Agents on the same computer?
...
Yes, it's possible:
Several agents can be installed on a single machine. They function as separate agents and TeamCity works with them as different agents, not utilizing the fact that they share the same machine.
After installing one agent you can install additional one,...
PHP: How to handle
...s a string. (in this example, the casting is superfluous, as echo automatically does it anyway)
$content = simplexml_load_string(
'<content><![CDATA[Hello, world!]]></content>'
);
echo (string) $content;
// or with parent element:
$foo = simplexml_load_string(
'<foo&g...
Why use 'git rm' to remove a file instead of 'rm'?
...ml
rm 'index.html'
$ git status -s
D index.html
However you can do this all in one go with just git rm
$ git status -s
$ git rm index.html
rm 'index.html'
$ ls
lib vendor
$ git status -s
D index.html
share
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Why is there no multiple inheritance in Java, but implementing multiple interfaces is allowed?
Java doesn't allow multiple inheritance, but it allows implementing multiple interfaces. Why?
18 Answers
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Get city name using geolocation
... as to which one will have the city.
"administrative_area_level_1" is usually what you are looking for but sometimes locality is the city you are after.
Anyhow - more details on google response types can be found here and here.
Below is the code that should do the trick:
<!DOCTYPE html> ...
Ruby Regexp group matching, assign variables on 1 line
...u can use String#match which will return a MatchData object, you can then call #captures to return an Array of captures. Something like this:
#!/usr/bin/env ruby
string = "RyanOnRails: This is a test"
one, two, three = string.match(/(^.*)(:)(.*)/i).captures
p one #=> "RyanOnRails"
p two #=...
Upload files with HTTPWebrequest (multipart/form-data)
... wresp.Close();
wresp = null;
}
} finally {
wr = null;
}
}
and sample usage:
NameValueCollection nvc = new NameValueCollection();
nvc.Add("id", "TTR");
nvc.Add("btn-submit-photo", "Upload");
HttpUploadFile("http://your....
Fastest method of screen capturing on Windows
...ollect single frames, but if you modify this and keep the two targets open all the time then you could "stream" it to disk using a static counter for the file name. - I can't recall where I found this, but it has been modified, thanks to whoever!
void dump_buffer()
{
IDirect3DSurface9* pRenderTa...