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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,...
HtmlString vs. MvcHtmlString
HtmlString vs. MvcHtmlString
3 Answers
3
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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);
...
pass post data with window.location.href
...;
submitMe.enctype = "multipart/form-data";
var nameJoiner = "_";
// ^ The string used to join form name and input name
// so that you can differentiate between forms when
// processing the data server-side.
submitMe.importFields = function(form){
for(k in form.elements){
if(input = ...
How to get the first non-null value in Java?
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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...
MySQL WHERE: how to write “!=” or “not equals”?
...he standard <> operator.
Perhaps your fields are not actually empty strings, but instead NULL?
To compare to NULL you can use IS NULL or IS NOT NULL or the null safe equals operator <=>.
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What does the “yield” keyword do?
...i)
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Everything you can use "for... in..." on is an iterable; lists, strings, files...
These iterables are handy because you can read them as much as you wish, but you store all the values in memory and this is not always what you want when you have a lot of values.
Generators
Generators ar...
Get the distance between two geo points
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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
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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
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