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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))
#> # A tibble: 3 x 2
#> b count_a
#>...
TypeLoadException says 'no implementation', but it is implemented
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any good final solution about it ? What solution was Microsoft recommended ?
– Kiquenet
Sep 18 '12 at 18:27
12
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How to run JUnit test cases from the command line
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and what if you are using android?
– n611x007
Aug 13 '14 at 10:04
1
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Difference between Pragma and Cache-Control headers?
...o. And that actually might mean to returning stale content to the clients, WHAT?? Now you forget this and read the above simple answer and enjoy your life, don't dig it too hard lol
– sotn
Mar 3 '16 at 21:29
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SQL Server: Make all UPPER case to Proper Case/Title Case
...s imported as all UPPER CASE and I would like to turn it into Proper Case. What script have any of you used to complete this?
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How should I store GUID in MySQL tables?
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need reply, what really is a char 16 binary? not char? not binary? I dont see that type in any of the mysql gui tools, nor any documentation in mysql site. @BillyONeal
– nawfal
Jun 24 '12 at 19:41
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How to convert ‘false’ to 0 and ‘true’ to 1 in Python
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Although it's probably what the OP wanted, it doesn't exactly match the question as asked for python 2.7. They explicitly asked for it to work on type unicode and did not specify the behaviour for type str.
– wim
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How do I sort a dictionary by value?
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print(w, d[w])
I am writing this detailed explanation to illustrate what people often mean by "I can easily sort a dictionary by key, but how do I sort by value" - and I think the original post was trying to address such an issue. And the solution is to do sort of list of the keys, based on t...
How do I sort an NSMutableArray with custom objects in it?
What I want to do seems pretty simple, but I can't find any answers on the web. I have an NSMutableArray of objects, and let's say they are 'Person' objects. I want to sort the NSMutableArray by Person.birthDate which is an NSDate .
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How to set transform origin in SVG
.... I tried replacing the instance of "view" with "mainGrid" with no effect. What am I missing? Thanks!
– sakeferret
Jul 18 '19 at 21:37
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