# Extension of data.frame

## Documentation for package ‘data.table’ version 1.9.4

- DESCRIPTION file.
- User guides, package vignettes and other documentation.

## Help Pages

A B C D F G H I J K L M N O P Q R S T U W Y misc

data.table-package | Enhanced data.frame

## -- A --

address | Address in RAM of a variable
all.equal | Equality Test Between Two Data Tables
all.equal.data.table | Equality Test Between Two Data Tables
alloc.col | Over-allocation access
anyDuplicated | Determine Duplicate Rows
anyDuplicated.data.table | Determine Duplicate Rows
as.character.ITime | Integer based date class
as.chron.IDate | Integer based date class
as.chron.ITime | Integer based date class
as.data.table | Enhanced data.frame
as.Date.IDate | Integer based date class
as.IDate | Integer based date class
as.IDate.Date | Integer based date class
as.IDate.default | Integer based date class
as.ITime | Integer based date class
as.ITime.character | Integer based date class
as.ITime.default | Integer based date class
as.ITime.POSIXlt | Integer based date class
as.ITime.times | Integer based date class
as.list.IDate | Integer based date class
as.POSIXct.IDate | Integer based date class
as.POSIXct.ITime | Integer based date class
as.POSIXlt.ITime | Integer based date class

## -- B --

between | Convenience function for range subset logic.

## -- C --

c.IDate | Integer based date class
chgroup | Faster match of character vectors
chmatch | Faster match of character vectors
chorder | Faster match of character vectors
CJ | Creates a Join data table
class:data.table | S4 Definition for data.table
copy | Copy an entire object
cut.IDate | Integer based date class

## -- D --

data.table | Enhanced data.frame
data.table-class | S4 Definition for data.table
dcast | Fast dcast for data.table
dcast.data.table | Fast dcast for data.table
duplicated | Determine Duplicate Rows
duplicated.data.table | Determine Duplicate Rows

## -- F --

fastorder | Fast reordering of a data.table by reference
forder | Fast reordering of a data.table by reference
format.ITime | Integer based date class
foverlaps | Fast overlap joins
fread | Fast and friendly file finagler

## -- G --

getNumericRounding | Change or turn off numeric rounding

## -- H --

haskey | Create key on a data table
hour | Integer based date class

## -- I --

IDate | Integer based date class
IDate-class | Integer based date class
IDateTime | Integer based date class
IDateTime.default | Integer based date class
is.data.table | Enhanced data.frame
is.na.data.table | Enhanced data.frame
ITime | Integer based date class
ITime-class | Integer based date class

## -- J --

J | Creates a Join data table

## -- K --

key | Create key on a data table
key2 | Create key on a data table
key<- | Create key on a data table

## -- L --

last | Last item of an object
like | Convenience function for calling regexpr.

## -- M --

mday | Integer based date class
mean.IDate | Integer based date class
melt | Fast melt for data.table
melt.data.table | Fast melt for data.table
merge | Merge Two Data Tables
merge.data.table | Merge Two Data Tables
month | Integer based date class

## -- N --

na.omit.data.table | Enhanced data.frame

## -- O --

Ops.data.table | Enhanced data.frame
order | Fast reordering of a data.table by reference

## -- P --

print.ITime | Integer based date class

## -- Q --

quarter | Integer based date class

## -- R --

rbind | Makes one data.table from a list of many
rbind.data.table | Makes one data.table from a list of many
rbindlist | Makes one data.table from a list of many
rep.IDate | Integer based date class
rep.ITime | Integer based date class
round.IDate | Integer based date class

## -- S --

seq.IDate | Integer based date class
set | Assignment by reference
set2key | Create key on a data table
set2keyv | Create key on a data table
setattr | Set attributes to objects by reference
setcolorder | Fast reordering of a data.table by reference
setDF | Convert a data.table to data.frame by reference
setDT | Convert lists and data.frames to data.table by reference
setkey | Create key on a data table
setkeyv | Create key on a data table
setnames | Set attributes to objects by reference
setNumericRounding | Change or turn off numeric rounding
setorder | Fast reordering of a data.table by reference
setorderv | Fast reordering of a data.table by reference
SJ | Creates a Join data table
split.IDate | Integer based date class
subset | Subsetting data.tables
subset.data.table | Subsetting data.tables

## -- T --

tables | Display all objects of class 'data.table'
test.data.table | Runs a set of tests.
timetaken | Pretty print of time taken
transform | Data table utilities
transform.data.table | Data table utilities
truelength | Over-allocation access

## -- U --

unique | Determine Duplicate Rows
unique.data.table | Determine Duplicate Rows

## -- W --

wday | Integer based date class
week | Integer based date class
within | Data table utilities
within.data.table | Data table utilities

## -- Y --

yday | Integer based date class
year | Integer based date class

## -- misc --

%between% | Convenience function for range subset logic.
%chin% | Faster match of character vectors
%like% | Convenience function for calling regexpr.
:= | Assignment by reference
[.data.table | Enhanced data.frame