Cole questions

Cole answers

• Rolling count of distinct years
• Replacing NA of numbered column in list of data frames
• Return original data set after top_n
• Sum/count between two dates in R
• Is there a faster method for making paired comparisons than expand.grid in Base R?
• How I can take mean for different subsets of a specific column in a data.table?
• applying a dist function rowise in custom function
• Create Combinations in R by Groups
• How to group and summarise each data frame in a list of data frames
• Is there any faster alternative to stats:uniroot function in R?