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How to avoid warning when introducing NAs by coercion
... na = x %in% na.strings
x[na] = 0
x = as.numeric(x)
x[na] = NA_real_
x
}
as.num(c("1", "2", "X"), na.strings="X")
#[1] 1 2 NA
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Vim: Creating parent directories on save
...ries for files like ftp://* and !isdirectory will prevent expensive mkdir call.
Update: sligtly better solution that also checks for non-empty buftype and uses mkdir():
function s:MkNonExDir(file, buf)
if empty(getbufvar(a:buf, '&buftype')) && a:file!~#'\v^\w+\:\/'
let dir=...
What are the differences between type() and isinstance()?
...identity of types and rejects instances of subtypes, AKA subclasses).
Normally, in Python, you want your code to support inheritance, of course (since inheritance is so handy, it would be bad to stop code using yours from using it!), so isinstance is less bad than checking identity of types because...
What is base 64 encoding used for?
...you have some binary data that you want to ship across a network, you generally don't do it by just streaming the bits and bytes over the wire in a raw format. Why? because some media are made for streaming text. You never know -- some protocols may interpret your binary data as control character...
How to sort an array of integers correctly
...
By default, the sort method sorts elements alphabetically. To sort numerically just add a new method which handles numeric sorts (sortNumber, shown below) -
var numArray = [140000, 104, 99];
numArray.sort(function(a, b) {
return a - b;
});
console.log(numArray);
...
Groovy / grails how to determine a data type?
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To determine the class of an object simply call:
someObject.getClass()
You can abbreviate this to someObject.class in most cases. However, if you use this on a Map it will try to retrieve the value with key 'class'. Because of this, I always use getClass() even thou...
What is the difference between DSA and RSA?
...being a bit more complex than,
but related to El Gamal.
Note that nearly all the calculations are mod q, and
hence are much faster.
But, In contrast to RSA, DSA can be used only for digital signatures
DSA Security
The presence of a subliminal channel exists in many schemes (any that need a ran...
How to center align the cells of a UICollectionView?
...nt, you could adjust that one too, if you want to center the content vertically in the screen.
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How to fix java.lang.UnsupportedClassVersionError: Unsupported major.minor version
I am trying to use Notepad++ as my all-in-one tool edit, run, compile, etc.
51 Answers
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How do I force a UITextView to scroll to the top every time I change the text?
...here's too much hoop jumping to get things to behave the way they automatically should in most cases.
– John Contarino
Jun 9 '15 at 21:52
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