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Omit rows containing specific column of NA
...ete.cases function and put it into a function thusly:
DF <- data.frame(x = c(1, 2, 3), y = c(0, 10, NA), z=c(NA, 33, 22))
completeFun <- function(data, desiredCols) {
completeVec <- complete.cases(data[, desiredCols])
return(data[completeVec, ])
}
completeFun(DF, "y")
# x y z
# 1...
Extract subset of key-value pairs from Python dictionary object?
...u're using Python 3, and you only want keys in the new dict that actually exist in the original one, you can use the fact to view objects implement some set operations:
{k: bigdict[k] for k in bigdict.keys() & {'l', 'm', 'n'}}
...
Does Python optimize tail recursion?
...ng to transform it like that - just: from operator import add; reduce(add, xrange(n + 1), csum) ?
– Jon Clements♦
Nov 27 '12 at 20:10
38
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Math - mapping numbers
...
If your number X falls between A and B, and you would like Y to fall between C and D, you can apply the following linear transform:
Y = (X-A)/(B-A) * (D-C) + C
That should give you what you want, although your question is a little ambigu...
Most efficient method to groupby on an array of objects
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How can I convert my device token (NSData) into an NSString?
...iceToken: Data) {
let token = deviceToken.map { String(format: "%02.2hhx", $0) }.joined()
print(token)
}
Old answer using NSData:
func application(application: UIApplication, didRegisterForRemoteNotificationsWithDeviceToken deviceToken: NSData) {
let tokenChars = UnsafePointer<CChar&...
Quickest way to convert a base 10 number to any base in .NET?
...rt a number to its equivalent string representation in a specified base.
Example:
string binary = Convert.ToString(5, 2); // convert 5 to its binary representation
Console.WriteLine(binary); // prints 101
However, as pointed out by the comments, Convert.ToString only supports the fo...
How do I set a conditional breakpoint in gdb, when char* x points to a string whose value equals “he
Can I specify that I want gdb to break at line x when char* x points to a string whose value equals "hello" ? If yes, how?
...
JavaScript property access: dot notation vs. brackets?
...n't be used with dot notation:
var foo = myForm.foo[]; // incorrect syntax
var foo = myForm["foo[]"]; // correct syntax
including non-ASCII (UTF-8) characters, as in myForm["ダ"] (more examples).
Secondly, square bracket notation is useful when dealing with
property names which vary in a pre...
Find mouse position relative to element
...ition, and then subtract it from the parent element's offset position.
var x = evt.pageX - $('#element').offset().left;
var y = evt.pageY - $('#element').offset().top;
If you're trying to get the mouse position on a page inside a scrolling pane:
var x = (evt.pageX - $('#element').offset().left) + s...