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Can dplyr package be used for conditional mutating?

... 220 Use ifelse df %>% mutate(g = ifelse(a == 2 | a == 5 | a == 7 | (a == 1 & b == 4), 2, ...
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What is the difference between ~> and >= when specifying rubygem in Gemfile?

... version provided and use that until it reaches a maximum version. So ~>0.8.5 is semantically equivalent to: gem "cucumber", ">=0.8.5", "<0.9.0" The easy way to think about it is that you're okay with the last digit incrementing to some arbitrary value, but the ones preceding it in the st...
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Why is a round-trip conversion via a string not safe for a double?

...mber->precision = precision; if (((FPDOUBLE*)&value)->exp == 0x7FF) { number->scale = (((FPDOUBLE*)&value)->mantLo || ((FPDOUBLE*)&value)->mantHi) ? SCALE_NAN: SCALE_INF; number->sign = ((FPDOUBLE*)&value)->sign; number->digits[0] =...
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New Array from Index Range Swift

... This works for me: var test = [1, 2, 3] var n = 2 var test2 = test[0..<n] Your issue could be with how you're declaring your array to begin with. EDIT: To fix your function, you have to cast your Slice to an array: func aFunction(numbers: Array<Int>, position: Int) -> Array&...
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Define a lambda expression that raises an Exception

... 170 There is more than one way to skin a Python: y = lambda: (_ for _ in ()).throw(Exception('fooba...
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Is there a simple way to remove multiple spaces in a string?

... Francisco Couzo 8,04633 gold badges2929 silver badges3737 bronze badges answered Oct 9 '09 at 21:52 Josh LeeJosh Lee ...
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What is the >>>= operator in C?

... The line: while( a[ 0xFULL?'\0':-1:>>>=a<:!!0X.1P1 ] ) contains the digraphs :> and <:, which translate to ] and [ respectively, so it's equivalent to: while( a[ 0xFULL?'\0':-1 ] >>= a[ !!0X.1P1 ] ) The literal 0xFUL...
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How to turn NaN from parseInt into 0 for an empty string?

Is it possible somehow to return 0 instead of NaN when parsing values in JavaScript? 18 Answers ...
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How to convert a unix timestamp (seconds since epoch) to Ruby DateTime?

...conds with'%Q tho. – Mini John Feb 10 '15 at 2:13 3 To follow up on @TheMiniJohn's answer. It loo...
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Email Address Validation in Android on EditText [duplicate]

...target). – rciovati Apr 13 '13 at 9:02 20 ...