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Convert data.frame column to a vector?
...
If you just use the extract operator it will work. By default, [] sets option drop=TRUE, which is what you want here. See ?'[' for more details.
> a1 = c(1, 2, 3, 4, 5)
> a2 = c(6, 7, 8, 9, 10)
> a3 = c(11, 12, 13, 14, 15)
> aframe = data.frame(a1, a2, a3)
&...
USB Debugging option greyed out
...eveloper”. Your’re not done yet.
Go back to your phone’s home page by pushing the home button.
Go to “Settings”.
Go to “Developer options”
Click the “USB debugging- Turn on debug mode when USB is connected”. A blue checkmark will appear.
(EDIT: If USB Debugging is greyed out...
Format date to MM/dd/yyyy in JavaScript [duplicate]
...' + year;
}
Update for ES2017 using String.padStart(), supported by all major browsers except IE.
function getFormattedDate(date) {
let year = date.getFullYear();
let month = (1 + date.getMonth()).toString().padStart(2, '0');
let day = date.getDate().toString().padStart...
jQuery Scroll to bottom of page/iframe
...d scroll to the top when this function was run. This problem was resolved by saying $(document).scrollTop($(document).height());
– Jack
Jan 21 '14 at 20:03
add a comment
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How to set radio button checked as default in radiogroup?
...urse there are ways to do that without ids of your buttons, but please not by using setChecked() One way would be radiogroup.check(((RadioButton)radioGroup.getChildAt(INDEX)).getId()) or something like that
– Sprigg
Apr 29 '13 at 13:05
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Round a Floating Point Number Down to the Nearest Integer?
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x//1
The // operator returns the floor of the division. Since dividing by 1 doesn't change your number, this is equivalent to floor but no import is needed.
Notes:
This returns a float
This rounds towards -∞
share
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IOS 7 Navigation Bar text and arrow color
...e Documentation for barTintColor says :
This color is made translucent by default unless you set the
translucent property to NO.
Sample Code :
self.navigationController.navigationBar.barTintColor = [UIColor blackColor];
self.navigationController.navigationBar.tintColor = [UIColor whiteColor...
What does the @ symbol before a variable name mean in C#? [duplicate]
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You still need to escape double quotes by doubling them.
– Justin Skiles
Jan 29 '14 at 19:32
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How to schedule a periodic task in Java?
...hen in main class you instantiate the task and run it periodically started by a specified date:
public void runTask() {
Calendar calendar = Calendar.getInstance();
calendar.set(
Calendar.DAY_OF_WEEK,
Calendar.MONDAY
);
calendar.set(Calendar.HO...
Do I have to Close() a SQLConnection before it gets disposed?
...using either the
Close or Dispose methods of the
Connection object, or by opening all
connections inside a using statement
in C#"
The actual implementation of SqlConnection.Dispose using .NET Reflector is as follows:
// System.Data.SqlClient.SqlConnection.Dispose disassemble
protected ove...