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Summarizing multiple columns with dplyr? [duplicate]
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The dplyr package contains summarise_all for this aim:
library(dplyr)
df %>% group_by(grp) %>% summarise_all(list(mean))
#> # A tibble: 3 x 5
#> grp a b c d
#> <int> <dbl> <dbl> <dbl> <dbl>
#>...
android asynctask sending callbacks to ui [duplicate]
...tivity I'm initializing the asynctask, and I want the asynctask to report callbacks back to my activity.
Is it possible? Or does the asynctask must be in the same class file as the activity?
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Reading a plain text file in Java
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I'd also recommend you download and read this wonderful (yet free) book called Thinking In Java
In Java 7:
new String(Files.readAllBytes(...))
(docs)
or
Files.readAllLines(...)
(docs)
In Java 8:
Files.lines(..).forEach(...)
(docs)
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How do I get the currently displayed fragment?
...t the currently displayed Fragment instance, not iteratively check through all fragments and then decide which fragment is now displayed on the screen. I think your answer needs my code to iteratively check each of my fragments, and find out the visible one ...
– Leem.fin
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Filter dataframe rows if value in column is in a set list of values [duplicate]
... regular expressions.
For example, if we want to return a DataFrame where all of the stock IDs which begin with '600' and then are followed by any three digits:
>>> rpt[rpt['STK_ID'].str.contains(r'^600[0-9]{3}$')] # ^ means start of string
... STK_ID ... ...
Modulo operation with negative numbers
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C99 requires that when a/b is representable:
(a/b) * b + a%b shall equal a
This makes sense, logically. Right?
Let's see what this leads to:
Example A. 5/(-3) is -1
=> (-1) * (-3) + 5%(-3) = 5
This can only happen if 5%(-3) is 2.
Example B. (-5)/3 is -1
=> (-1) * 3 + (-5...
how to show lines in common (reverse diff)?
...ile2, and they have both overlapping and non-overlapping rows. If you want all and only the non-overlapping rows, using fgrep -v file1 file2 will only return the non-overlapping rows in file2, and none of the additional non-overlapping rows in file1. This may be obvious to some, but better to state ...
How do I create a new Swift project without using Storyboards?
Creating a new project in XCode 6 doesn't allow to disable Storyboards. You can only select Swift or Objective-C and to use or not Core Data.
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Hyphen, underscore, or camelCase as word delimiter in URIs?
...designing an HTTP-based API for an intranet app. I realize it's a pretty small concern in the grand scheme of things, but: should I use hyphens, underscores, or camelCase to delimit words in the URIs?
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How can I show dots (“…”) in a span with hidden overflow?
... standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book</span>
JSFiddle
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