Learn RDataTable
I Introduction
CoverPage
1
Introduction
2
Speed
3
Memory
3.1
Pure function
3.2
Impure functions
3.3
Pass by value
3.4
Pass by reference
4
Keystrokes
II Beginner
5
Syntax
6
From
7
Where
8
Select
9
Group By
III Intermediate
10
From
11
Where
12
Select
13
Group By
14
Update
15
Add Column
16
Append
17
Join
IV Advanced
18
Melt
19
Dcast
20
tstrsplit
21
.SD
22
.SDcols
23
Delayed calculation {}
24
setFunctions
25
IDate
26
ITime
27
List Columns
28
Inside a Function
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Learn RDataTable
Chapter 9
Group By