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How do I replace NA values with zeros in an R dataframe?

... See my comment in @gsk3 answer. A simple example: > m <- matrix(sample(c(NA, 1:10), 100, replace = TRUE), 10) > d <- as.data.frame(m) V1 V2 V3 V4 V5 V6 V7 V8 V9 V10 1 4 3 NA 3 7 6 6 10 6 5 2 9 8 9 5 10 NA 2 1 7 ...
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Rails: Check output of path helper from console

... a Rails console, you can call app.post_path. This will work in Rails ~= 2.3 and >= 3.1.0. share | improve this answer | follow | ...
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Get decimal portion of a number with JavaScript

I have float numbers like 3.2 and 1.6 . 22 Answers 22 ...
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Java lib or app to convert CSV to XML file? [closed]

... | edited Feb 7 '13 at 10:36 CloudyMarble 33.8k2323 gold badges8989 silver badges126126 bronze badges ...
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ActiveRecord, has_many :through, and Polymorphic Associations

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Count number of records returned by group by

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Two-dimensional array in Swift

...ray of arrays of Ints set to 0. Arrays size is 10x5 var arr = Array(count: 3, repeatedValue: Array(count: 2, repeatedValue: 0)) // ...and for Swift 3+: var arr = Array(repeating: Array(repeating: 0, count: 2), count: 3) Change element at position arr[0][1] = 18 OR let myVar = 18 arr[0][1] = m...
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Some built-in to pad a list in python

... answered Aug 9 '10 at 9:43 John La RooyJohn La Rooy 249k4646 gold badges326326 silver badges469469 bronze badges ...
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Split list into multiple lists with fixed number of elements

...an iterator, but you can convert the result to a list, scala> List(1,2,3,4,5,6,"seven").grouped(4).toList res0: List[List[Any]] = List(List(1, 2, 3, 4), List(5, 6, seven)) share | improve this ...
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Is there a decorator to simply cache function return values?

... Starting from Python 3.2 there is a built-in decorator: @functools.lru_cache(maxsize=100, typed=False) Decorator to wrap a function with a memoizing callable that saves up to the maxsize most recent calls. It can save time when an expensive or...