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Paste multiple columns together
...
# your starting data..
data <- data.frame('a' = 1:3, 'b' = c('a','b','c'), 'c' = c('d', 'e', 'f'), 'd' = c('g', 'h', 'i'))
# columns to paste together
cols <- c( 'b' , 'c' , 'd' )
# create a new column `x` with the three columns collapsed togeth...
Downloading a file from spring controllers
...
I was able to stream line this by using the built in support in Spring with it's ResourceHttpMessageConverter. This will set the content-length and content-type if it can determine the mime-type
@RequestMapping(value = "/files/{file_name}", method = RequestMethod.GET)
@...
jQuery: count number of rows in a table
...
If you use <tbody> or <tfoot> in your table, you'll have to use the following syntax or you'll get a incorrect value:
var rowCount = $('#myTable >tbody >tr').length;
...
Download a specific tag with Git
... with $ git tag -l and then checkout a specific tag:
$ git checkout tags/<tag_name>
Even better, checkout and create a branch (otherwise you will be on a branch named after the revision number of tag):
$ git checkout tags/<tag_name> -b <branch_name>
...
What is the easiest way to duplicate an activerecord record?
...
To get a copy, use the clone (or dup for rails 3.1+) method:
# rails < 3.1
new_record = old_record.clone
#rails >= 3.1
new_record = old_record.dup
Then you can change whichever fields you want.
ActiveRecord overrides the built-in Object#clone to give you a new (not saved to the DB) re...
std::wstring VS std::string
...ed in UTF-8 (i.e. Unicode string of chars). The following code:
#include <cstring>
#include <iostream>
int main(int argc, char* argv[])
{
const char text[] = "olé" ;
std::cout << "sizeof(char) : " << sizeof(char) << std::endl ;
std::cout << "text ...
How to size an Android view based on its parent's dimensions
... 2, parentHeight);
}
}
Your XML would look something like this:
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<view
class="com.company.MyCustomView"
android:layout_width="match_parent"
android:layout_he...
Determine if an element has a CSS class with jQuery
...'s elements' className string. So if, for instance, you have an element,
<span class="foo bar" />
then this will return true:
$('span').hasClass('foo bar')
and these will return false:
$('span').hasClass('bar foo')
$('span').hasClass('foo bar')
...
New lines inside paragraph in README.md
...
Interpreting newlines as <br /> used to be a feature of Github-flavored markdown, but the most recent help document no longer lists this feature.
Fortunately, you can do it manually. The easiest way is to ensure that each line ends with two spa...
Returning value from Thread
...ecutorService executor = Executors.newSingleThreadExecutor();
Callable<Integer> callable = new Callable<Integer>() {
@Override
public Integer call() {
return 2;
}
};
Future<Integer> future = executor.submit(callable);
// future.ge...