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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...
WPF: Grid with column/row margin/padding?
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RowDefinition and ColumnDefinition are of type ContentElement, and Margin is strictly a Framewo...
How to exclude specific folders or files from validation in Eclipse?
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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...
Postgres: Distinct but only for one column
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edited Jun 20 at 9:12
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Get selected value in dropdown list using JavaScript
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Vitalii FedorenkoVitalii Fedorenko
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How do I add a path to PYTHONPATH in virtualenv
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91
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Shell Script — Get all files modified after
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91
If you have GNU find, then there are a legion of relevant options. The only snag is that the i...
List tables in a PostgreSQL schema
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