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Changing column names of a data frame
...
Use the colnames() function:
R> m>X m> <- data.frame(bad=1:3, worse=rnorm(3))
R> m>X m>
bad worse
1 1 -2.440467
2 2 1.320113
3 3 -0.306639
R> colnames(m>X m>) <- c("good", "better")
R> m>X m>
good better
1 1 -2.440467
2 2 1.320113
3 3...
What is the method for converting radians to degrees?
...r just don't want to type it in with all decimals
– Am>x m>el Kemper
Jan 7 '13 at 23:46
21
Maybe this ...
How to convert numbers between hem>x m>adecimal and decimal
How do you convert between hem>x m>adecimal numbers and decimal numbers in C#?
17 Answers
1...
How do I check if an object has a specific property in JavaScript?
...imply reducing the property check to typeof this[property] or, even worse, m>x m>.key will give you completely misleading results.
It depends on what you're looking for. If you want to know if an object physically contains a property (and it is not coming from somewhere up on the prototype chain) then o...
What is the difference between old style and new style classes in Python?
...The concept of (old-style) class is unrelated to the concept of type:
if m>x m> is an instance of an old-style class, then m>x m>.__class__
designates the class of m>x m>, but type(m>x m>) is always <type
'instance'>.
This reflects the fact that all old-style instances, independently of
their class,...
Java: parse int value from a char
...m a character in a string (assuming that we know that the character at indem>x m> n is a number).
7 Answers
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The cast to value type 'Int32' failed because the materialized value is null
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A linq-to-sql query isn't em>x m>ecuted as code, but rather translated into SQL. Sometimes this is a "leaky abstraction" that yields unem>x m>pected behaviour.
One such case is null handling, where there can be unem>x m>pected nulls in different places. ...DefaultI...
Android emulator freezing OS m>X m> v10.9 (Mavericks) with HAm>X m>M
I just updated to OS m>X m> v10.9 (Mavericks), and now whenever I start up any of my emulators, as soon as the emulator starts up, my entire computer freezes with a spinning progress indicator in the center of the screen (not a beachball, the progress indicator is similar to what you see when shutting...
Algorithm for Determining Tic Tac Toe Game Over
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You know a winning move can only happen after m>X m> or O has made their most recent move, so you can only search row/column with optional diag that are contained in that move to limit your search space when trying to determine a winning board. Also since there are a fim>x m>ed n...
How to create a button programmatically?
...ewDidLoad() {
super.viewDidLoad()
let button = UIButton(frame: CGRect(m>x m>: 100, y: 100, width: 100, height: 50))
button.backgroundColor = .greenColor()
button.setTitle("Test Button", forState: .Normal)
button.addTarget(self, action: #selector(buttonAction), forControlEvents: .TouchUpInside)...