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dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
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Since dplyr 0.8 group_by gained the .drop argument that does just what you asked for:
df = data.frame(a=rep(1:3,4), b=rep(1:2,6))
df$b = factor(df$b, levels=1:3)
df %>%
group_by(b, .drop=FALSE) %>%
summarise(count_a=length(a))
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Node.JS constant for platform-specific new line?
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Not sure if this is new in the 0.8.x but there is now a constant http://nodejs.org/api/os.html#os_os_eol
var endOfLine = require('os').EOL;
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improv...
What is the syntax for “not equal” in SQLite?
...use NOT EQUAL ?
– ThierryC
Jan 16 '18 at 11:09
3
@ban-geoengineering <> is SQL Ansi standar...
How to assertThat something is null with Hamcrest?
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edited Dec 2 '14 at 3:38
Jared Burrows
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IntelliJ 13 - Add Navigate Back/Forward to toolbar?
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85
I am using Idea 13 and my toolbar already has these buttons:
The icon groups are:
file | u...
Is there a ternary conditional operator in T-SQL?
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answered Apr 25 '13 at 8:22
GuffaGuffa
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textarea - disable resize on x or y?
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189
resize: vertical;
or
resize: horizontal;
Quick fiddle: http://jsfiddle.net/LLrh7Lte/
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jQuery selector for the label of a checkbox
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KipKip
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iPhone - Get Position of UIView within entire UIWindow
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edited Aug 25 '14 at 7:08
answered Sep 23 '09 at 11:32
Ni...
Verify a method call using Moq
...atinum Azure
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