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Summarizing multiple columns with dplyr? [duplicate]

...df %>% group_by(grp) %>% summarise_all(list(mean)) #> # A tibble: 3 x 5 #> grp a b c d #> <int> <dbl> <dbl> <dbl> <dbl> #> 1 1 3.08 2.98 2.98 2.91 #> 2 2 3.03 3.04 2.97 2.87 #> 3 3 2.85 2.95 2.95 3.06...
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Implementing slicing in __getitem__

...m__(self, val): ... print val ... >>> c = C() >>> c[3] 3 >>> c[3:4] slice(3, 4, None) >>> c[3:4:-2] slice(3, 4, -2) >>> c[():1j:'a'] slice((), 1j, 'a') share | ...
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Read user input inside a loop

... answered Jul 30 '11 at 13:42 dankdank 1,13411 gold badge77 silver badges22 bronze badges ...
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Python using enumerate inside list comprehension

...t that gets returned is as expected: > [(0, 'a'), (1, 'b'), (2, 'c'), (3, 'd')] share | improve this answer | follow | ...
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what is the function of webpages:Enabled in MVC 3 web.config

I just started a new MVC 3 project. Can anyone tell me what 3 Answers 3 ...
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Selecting pandas column by location

... mind: >>> df A B C D 0 0.424634 1.716633 0.282734 2.086944 1 -1.325816 2.056277 2.583704 -0.776403 2 1.457809 -0.407279 -1.560583 -1.316246 3 -0.757134 -1.321025 1.325853 -2.513373 4 1.366180 -1.265185 -2.184617 0.881514 >>> df.iloc[:, ...
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Return two and more values from a method

... def sumdiff(x, y) return x+y, x-y end #=> nil sumdiff(3, 4) #=> [7, -1] a = sumdiff(3,4) #=> [7, -1] a #=> [7, -1] a,b=sumdiff(3,4) #=> [7, -1] a #=> 7 b #=> -1 a,b,c=sumdiff(3,4) #=> [7, -1] a #=> 7 b #=> -1 c #=> nil ...
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Asterisk in function call

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Joda-Time: what's the difference between Period, Interval and Duration?

... 3 classes are needed because they represent different concepts so it is a matter of picking the appropriate one for the job rather than of relative performance. From the documentation with comments added by me in italics: ...
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Python Dictionary to URL Parameters

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