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How to remove last n characters from every element in the R vector
... an example of what I would do. I hope it's what you're looking for.
char_array = c("foo_bar","bar_foo","apple","beer")
a = data.frame("data"=char_array,"data2"=1:4)
a$data = substr(a$data,1,nchar(a$data)-3)
a should now contain:
data data2
1 foo_ 1
2 bar_ 2
3 ap 3
4 b 4
...
PHP abstract properties
...get_class($this) . ' must have a $tablename');
}
}
To enforce this for all derived classes of Foo_Abstract you would have to make Foo_Abstract's constructor final, preventing overriding.
You could declare an abstract getter instead:
abstract class Foo_Abstract {
abstract public function get_...
Get generated id after insert
...LiteDatabase().insert("user", "", values) ;
If query exec use select last_insert_rowid()
String sql = "INSERT INTO [user](firstName,lastName) VALUES (\"Ahmad\",\"Aghazadeh\"); select last_insert_rowid()";
DBHelper itemType =new DBHelper();// your dbHelper
c = db.rawQuery(sql, null);
if (c.move...
How can I get the latest JRE / JDK as a zip file rather than EXE or MSI installer? [closed]
... of JDK from Oracle (for example jdk-7u7-windows-x64.exe)
Download and install 7-Zip (or download 7-Zip portable version if you are not administrator)
With 7-Zip extract all the files from jdk-XuXX-windows-x64.exe into the directory C:\JDK
Execute the following commands in cmd.exe:
cd C:\JDK\.rsrc...
Best way to store date/time in mongodb
...ISODate()})
> db.test.insert({date: new Date()})
> db.test.find()
{ "_id" : ObjectId("..."), "date" : ISODate("2014-02-10T10:50:42.389Z") }
{ "_id" : ObjectId("..."), "date" : ISODate("2014-02-10T10:50:57.240Z") }
The native type supports a whole range of useful methods out of the box, which...
sed one-liner to convert all uppercase to lowercase?
I have a textfile in which some words are printed in ALL CAPS. I want to be able to just convert everything in the textfile to lowercase, using sed . That means that the first sentence would then read, 'i have a textfile in which some words are printed in all caps.'
...
How do I include a JavaScript file in another JavaScript file?
Is there something in JavaScript similar to @import in CSS that allows you to include a JavaScript file inside another JavaScript file?
...
Multiple returns from a function
...
Technically, you can't return more than one value. However, there are multiple ways to work around that limitation. The way that acts most like returning multiple values, is with the list keyword:
function getXYZ()
{
return arr...
Open a new tab in gnome-terminal using command line [closed]
...ferent commands in different tabs. No matter where I add the commands they all get executed in the first tab. Can you include a solution for this?
– Calin
May 3 '11 at 21:25
10
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Why should the Gradle Wrapper be committed to VCS?
...e whole point of the gradle wrapper is to be able, without having ever installed gradle, and without even knowing how it works, where to download it from, which version, to clone the project from the VCS, to execute the gradlew script it contains, and to build the project without any additional step...