data.table v1.12.8


Monthly downloads



Extension of `data.frame`

Fast aggregation of large data (e.g. 100GB in RAM), fast ordered joins, fast add/modify/delete of columns by group using no copies at all, list columns, friendly and fast character-separated-value read/write. Offers a natural and flexible syntax, for faster development.

Functions in data.table

Name Description
J Creates a join data.table
foverlaps Fast overlap joins
fifelse Fast ifelse
duplicated Determine Duplicate Rows Fast dcast for data.table
chmatch Faster match of character vectors
fcoalesce Coalescing missing values
data.table-class S4 Definition for data.table
copy Copy an entire object
data.table-package Enhanced data.frame
datatable.optimize Optimisations in data.table
fwrite Fast CSV writer
groupingsets Grouping Set aggregation for data tables
roll Rolling functions
fsort Fast parallel sort
like Convenience function for calling grep. Fast melt for data.table
patterns Obtain matching indices corresponding to patterns data.table Printing Options
rowid Generate unique row ids within each group
.Last.updated Number of rows affected by last update
last First/last item of an object
set2key Deprecated.
rbindlist Makes one data.table from a list of many
rleid Generate run-length type group id
fread Fast and friendly file finagler
frank Fast rank
merge Merge two data.tables
setattr Set attributes of objects by reference
setNumericRounding Change or turn off numeric rounding
setcolorder Fast column reordering of a data.table by reference
setkey Create key on a data.table
setDF Coerce a data.table to data.frame by reference Remove rows with missing values on columns specified
setops Set operations for data tables
special-symbols Special symbols
transpose Efficient transpose of list
setDT Coerce lists and data.frames to data.table by reference
truelength Over-allocation access
nafill Fill missing values Subsetting data.tables
setorder Fast row reordering of a data.table by reference
test Test assertions for equality, exceptions and console output
tables Display 'data.table' metadata Runs a set of tests.
shift Fast lead/lag for vectors and lists
shouldPrint For use by packages that mimic/divert auto printing e.g. IRkernel and knitr Data table utilities
timetaken Pretty print of time taken
setDTthreads Set or get number of threads that data.table should use
split Split data.table into chunks in a list
tstrsplit strsplit and transpose the resulting list efficiently Perform update of development version of a package
address Address in RAM of a variable Efficient xts to conversion
as.matrix Convert a data.table to a matrix Coerce to data.table Efficient data.table to xts conversion
all.equal Equality Test Between Two Data Tables
IDateTime Integer based date class
:= Assignment by reference
between Convenience functions for range subsets.
No Results!

Vignettes of data.table

No Results!

Last month downloads


Include our badge in your README