calculating sum of previous 3 rows in R data.table (by grid-square)

by

More Related Contents:

  1. Replacing NAs with latest non-NA value
  2. Adaptive moving average – top performance in R
  3. Is there a _fast_ way to run a rolling regression inside data.table?
  4. data.table vs dplyr: can one do something well the other can’t or does poorly?
  5. How to delete a row by reference in data.table?
  6. Why does X[Y] join of data.tables not allow a full outer join, or a left join?
  7. dplyr mutate/replace several columns on a subset of rows
  8. Proper/fastest way to reshape a data.table
  9. Filtering out duplicated/non-unique rows in data.table
  10. Data.table meta-programming
  11. data.table with two string columns of set elements, extract unique rows with each row unsorted
  12. Evaluating both column name and the target value within `j` expression within `data.table`
  13. Creating dummy variables in R data.table
  14. Fill in missing values by group in data.table
  15. data.table and parallel computing
  16. Why is plyr so slow?
  17. How to reorder data.table columns (without copying)
  18. Using setDT inside a function
  19. How to add a index by set of data when using rbindlist?
  20. Dynamically add column names to data.table when aggregating
  21. R: Reshaping Multiple Columns from Long to Wide
  22. Fill NA in a time series only to a limited number
  23. Long Numbers As A Character String
  24. R data.table apply function to rows using columns as arguments
  25. R: how to rbind two huge data-frames without running out of memory
  26. data.table package in R 3.5 does not install
  27. Aggregate by week in R
  28. How to use data.table within functions and loops?
  29. What you can do with a data.frame that you can’t with a data.table?
  30. data.table: anonymous function in j

Leave a Comment