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Group by multiple columns in dplyr, using string vector input
...oup_by_at(vars(one_of(columns))) %>%
summarize(Value = mean(value))
#compare plyr for reference
df2 <- plyr::ddply(data, columns, plyr::summarize, value=mean(value))
table(df1 == df2, useNA = 'ifany')
## TRUE
## 27
The output from your example question is as expected (see comparison to...
How to exclude specific folders or files from validation in Eclipse?
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60
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WPF: Grid with column/row margin/padding?
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91
RowDefinition and ColumnDefinition are of type ContentElement, and Margin is strictly a Framewo...
Postgres: Distinct but only for one column
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edited Jun 20 at 9:12
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answered Jun 4 '13 at 12:36
Clodoaldo NetoClodoa...
How does Google calculate my location on a desktop?
... wifi presence. Every time a query is performed to the system (probably in compliance with the W3C draft for the geolocation API) your computer sends the wifi identifiers it sees, and the system does two things:
queries its database if geolocation exists for some of the wifis you passed, and retur...
How do I add a path to PYTHONPATH in virtualenv
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91
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Sorting related items in a Django template
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Thanks for your comment, but this only works if I want to make the display order a permanent property of the attendee, which I don't. I might, for example, wish to display the attendees sorted by the date when their registration was receive...
List tables in a PostgreSQL schema
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Get selected value in dropdown list using JavaScript
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Vitalii FedorenkoVitalii Fedorenko
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