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Select first 4 rows of a data.frame in R
How can I select the first 4 rows of a data.frame :
5 Answers
5
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Obtain form input fields using jQuery?
...s[field.name] = field.value;
});
Note that this snippet will fail on <select multiple> elements.
It appears that the new HTML 5 form inputs don't work with serializeArray in jQuery version 1.3. This works in version 1.4+
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How dangerous is it to compare floating point values?
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[The 'right answer' glosses over selecting K. Selecting K ends up being just as ad-hoc as selecting VISIBLE_SHIFT but selecting K is less obvious because unlike VISIBLE_SHIFT it is not grounded on any display property. Thus pick your poison - select K or s...
How do you view ALL text from an ntext or nvarchar(max) in SSMS?
...tions on the Query menu, or right-click in the SQL Server Query window and select Query Options.
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Maximum Characters Retrieved
Enter a number from 1 through 65535 to specify the maximum number of characters that will be displayed in each cell.
Maximum is, as you see, 64k. T...
What is SELF JOIN and when would you use it? [duplicate]
...et information for both people in one row, you could self join like this:
select e1.EmployeeID,
e1.FirstName,
e1.LastName,
e1.SupervisorID,
e2.FirstName as SupervisorFirstName,
e2.LastName as SupervisorLastName
from Employee e1
left outer join Employee e2 on e1.SupervisorID ...
Xcode 6 Storyboard the wrong size?
...way at some point."
You probably haven't added the layout constraints.
Select your label, tap the layout constraints button on the bottom:
On that menu add width and height (it should NOT be the same as mine) by checking their checkbox and click add constraints. Then Control-drag your label t...
Correct way to add external jars (lib/*.jar) to an IntelliJ IDEA project
...ps for adding external jars in IntelliJ IDEA:
Click File from the toolbar
Select Project Structure option (CTRL + SHIFT + ALT + S on Windows/Linux, ⌘ + ; on Mac OS X)
Select Modules at the left panel
Select Dependencies tab
Select + icon
Select 1 JARs or directories option
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How do I use prepared statements in SQlite in Android?
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@jasonhudgins Why not just replace your SELECT with an INSERT? I just came from this thread, where you've confused a beginner
– keyser
May 3 '14 at 15:29
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CSS selector - element with a given child [duplicate]
I'm looking to make a selector which will select all elements if they have a specific child element. For example, select all <div> with a child <span> .
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Not equal != operator on NULL
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As a manual workaround, you could commonly SELECT * FROM MyTable WHERE coalesce(MyColumn, 'x') <> 'x' to assign a constant if it is NULL value, providing you give an appropriate datatype for the sentinel value x (in this case a string/char). This is TSQL syntax ...