hadley

hadley has asked 13 questions and find answers to 408 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

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
(Pre)supply variables to function factory and within
Separate a column in dataframe where each observation can have multiple concurrent values
R scope: force variable substitution in function without local environment
dplyr: calculate group weights
Optimizing the computation of a recursive sequence