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Selecting data frame rows based on partial string match in a column
...emember that subsetting approaches for data.frames and data.tables are not identical):
library(data.table)
mtcars[rownames(mtcars) %like% "Merc", ]
iris[iris$Species %like% "osa", ]
If that is what you had, then perhaps you had just mixed up row and column positions for subsetting data.
If you...
Why would you use Expression rather than Func?
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When you want to treat lambda expressions as expression trees and look inside them instead of executing them. For example, LINQ to SQL gets the expression and converts it to the equivalent SQL statement and submits it to server (rather than executing the lambda).
Conceptually, Expression<Func&l...
Purpose of Django setting ‘SECRET_KEY’
What exactly is the point of the SECRET_KEY in django? I did a few google searches and checked out the docs ( https://docs.djangoproject.com/en/dev/ref/settings/#secret-key ), but I was looking for a more in-depth explanation of this, and why it is required.
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How to check a radio button with jQuery?
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Please, elaborate. General idea is to check a radio button addressing it with its attributes - name and optionally, value. I'm not sure what are you trying to accomplish with this, since there are only name attribute and :checked pseudo selector used. ...
download and install visual studio 2008 [closed]
....com/downloads/info.aspx?na=90&p=&SrcDisplayLang=en&SrcCategoryId=&SrcFamilyId=7bbe5eda-5062-4ebb-83c7-d3c5ff92a373&u=http%3a%2f%2fdownload.microsoft.com%2fdownload%2f1%2ff%2f0%2f1f07c259-7ff2-4902-9205-ad1dfb87ccab%2fVS2008SP1MSDNENUX1506188.iso
To upgrade from trial version to...
Does deleting a branch in git remove it from the history?
...nd tags (by convention) live in separate 'folders' of the repository alongside the special 'trunk'.
If the branch was merged into another branch before it was deleted then all of the commits will still be reachable from the other branch when the first branch is deleted. They remain exactly as they ...
jQuery get specific option tag text
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It's looking for an element with id list which has a property value equal to 2.
What you want is the option child of the list:
$("#list option[value='2']").text()
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Programmatically go back to the previous fragment in the backstack
...kStack() methods (there are several to choose from)
http://developer.android.com/reference/android/app/FragmentManager.html#popBackStack()
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PDO support for multiple queries (PDO_MYSQL, PDO_MYSQLND)
...PDO::ATTR_EMULATE_PREPARES is set to 1 (default). Alternatively you can avoid using prepared statements and use $pdo->exec directly.
Using exec
$db = new PDO("mysql:host=localhost;dbname=test", 'root', '');
// works regardless of statements emulation
$db->setAttribute(PDO::ATTR_EMULATE_PREPA...
Add data annotations to a class generated by entity framework
...ass ItemRequestMetaData
{
[Required]
public int RequestId {get;set;}
//...
}
}
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