hadley

hadley has asked 13 questions and find answers to 414 problems.

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I'm chief scientist at RStudio.

hadley questions

Working with rich objects in data.table columns
Combined aggregated and non-aggregate query in SQL
ActiveRecord::StatementInvalid: Could not find table 'tablename'
Efficiently locate group-wise constant columns in a data.frame
Determine if a transaction is active (Postgres)
Blinding a latex paper
Automatically escape unicode characters
Which packages make good use of S4 objects?
Preventing performance regressions in R
Perform a semi-join with data.table

hadley answers

match.fun provide error with functions defined inside functions
Better way to turn two columns into one in R/Splus?
adding a list of vectors to a data.frame in R
R: polynomial shortcut notation in nls() formula
extracting values from column using tidyr
pass function to ddply wrapped inside a function as part of that functions call
Reading data via OData: how to specify the authentication scheme via curl/RCurl?
matching certain numbers at the end of a string
dplyr + magrittr + qplot = no plot?
tidyr wide to long: repeated measures and efficiency