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Convert data.frame columns from factors to characters
... with an apply statement:
bob <- data.frame(lapply(bob, as.character), stringsAsFactors=FALSE)
This will convert all variables to class "character", if you want to only convert factors, see Marek's solution below.
As @hadley points out, the following is more concise.
bob[] <- lapply(bob,...
Implement Stack using Two Queues
...(q2.remove());
}
}
}
public static void main(String[] args) {
StackImplUsingQueues s1 = new StackImplUsingQueues();
// Stack s1 = new Stack();
s1.push(1);
s1.push(2);
s1.push(3);
s1.push(4);
s1.push(5);
...
How to get the first non-null value in Java?
...
I was looking for the same but for strings, and found out that there are SpringUtils.firstNonBlank(T...) and SpringUtils.firstNonBlank(T...) methods.
– kodlan
Jul 29 at 17:23
...
bash/fish command to print absolute path to a file
...")" && pwd)/$(basename "$1")"
fi
}
Now it will return an empty string if one the parent dirs do not exist.
How do you handle trailing '..' or '.' in input ?
Well, it does give an absolute path in that case, but not a minimal one. It will look like:
/Users/bob/Documents/..
If you wan...
Get the distance between two geo points
...
This is great and super helpful, but what is the String provider for in the constrructor?
– miss.serena
Oct 30 '13 at 19:11
add a comment
...
How to add to the PYTHONPATH in Windows, so it finds my modules/packages?
....;C:\My_python_lib If you don't, windows will expand %PYTHONPATH% to empty string as expected, it will keep it as %PYTHONPATH% in the PYTHONPATH and everything will break! Sounds crazy but thats how win7 cmd works...
– ntg
Nov 10 '17 at 12:19
...
How to copy text from Emacs to another application on Linux
... (message "graphics active")
)
(insert (shell-command-to-string "xsel -o -b"))
)
)
(global-set-key [f8] 'copy-to-clipboard)
(global-set-key [f9] 'paste-from-clipboard)
share
|
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Fill remaining vertical space with CSS using display:flex
... html,body,section {height:100%;} where section is direct child of body jsfiddle.net/7yLFL/445 this gives a header and footer fixed.
– G-Cyrillus
Feb 22 '16 at 16:01
1
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Moving decimal places over in a double
...ystem.out.println(x);
which prints:
12.34
This works because Double.toString(d) performs a small amount of rounding on your behalf, but it is not much. If you are wondering what it might look like without rounding:
System.out.println(new BigDecimal(0.1));
System.out.println(new BigDecimal(x));...
Are HTTP cookies port specific?
...ly in Chrome, as most other browsers don't send cookies to "localhost" (=a string without two dots)
– Max
Mar 6 '14 at 11:35
4
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