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How to drop columns by name in a data frame
..."z","u"))]
x y
1 1 2
2 2 3
3 3 4
4 4 5
5 5 6
Or, much simpler, use the select argument of the subset function : you can then use the - operator directly on a vector of column names, and you can even omit the quotes around the names !
R> subset(df, select=-c(z,u))
x y
1 1 2
2 2 3
3 3 4
4 4 ...
Bootstrap datepicker hide after selection
How do I hide the calendar after a date is selected? Is there a specific function that I can use? My code below:
18 Answer...
Set the selected index of a Dropdown using jQuery
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First of all - that selector is pretty slow. It will scan every DOM element looking for the ids. It will be less of a performance hit if you can assign a class to the element.
$(".myselect")
To answer your question though, there are a few w...
How to use a class from one C# project with another C# project
...Explorer' tree, expand the P2 project and then right-click the project and select 'Add Reference' from the menu.
On the 'Add Reference' dialog, select the 'Projects' tab and select your P1 project.
If you are using namespaces then you will need to import the namespaces for your P1 types by adding ...
how to convert a string to date in mysql?
I have a string column which acts as a date and I want to select it as a date .
5 Answers
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How can I resolve “Error: No developer directory found at /Developer”?
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sudo xcode-select -switch /Applications/Xcode.app/Contents/Developer
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How do you kill all current connections to a SQL Server 2005 database?
...problems ALTER DATABASE aspnetdb SET SINGLE_USER WITH ROLLBACK IMMEDIATE select GETDATE() ALTER DATABASE aspnetdb SET MULTI_USER what do you have instead of the commented out code?
– SQLMenace
Aug 17 '10 at 18:33
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Xcode 4: create IPA file instead of .xcarchive
...-> Archive. After the Archive operation completes, go to the Organizer, select your archive, select Share and in the "Select the content and options for sharing:" pane set Contents to "iOS App Store Package (.ipa) and Identity to iPhone Distribution (which should match your ad hoc/app store provi...
How make Eclipse/EGit recognize existing repository information after update?
...ositories" dialogue, under Search criteria, enter the workspace directory, select "Look for nested repositores", and hit Search:
Select the repositories you want to add and click OK
"Share" each of the projects again using "use or create repository"
Open you existing project in Eclipse's Projec...
Color different parts of a RichTextBox string
...pendText(this RichTextBox box, string text, Color color)
{
box.SelectionStart = box.TextLength;
box.SelectionLength = 0;
box.SelectionColor = color;
box.AppendText(text);
box.SelectionColor = box.ForeColor;
}
}
And this is how you would use it:
var...