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R version 3.1.1 (2014-07-10) -- "Sock it to Me"
Copyright (C) 2014 The R Foundation for Statistical Computing
Platform: x86_64-pc-linux-gnu (64-bit)
R is free software and comes with ABSOLUTELY NO WARRANTY.
You are welcome to redistribute it under certain conditions.
Type 'license()' or 'licence()' for distribution details.
R is a collaborative project with many contributors.
Type 'contributors()' for more information and
'citation()' on how to cite R or R packages in publications.
Type 'demo()' for some demos, 'help()' for on-line help, or
'help.start()' for an HTML browser interface to help.
Type 'q()' to quit R.
> if (suppressPackageStartupMessages(requireNamespace("knitr", quietly = TRUE))) {
+ require(knitr)
+ knit("knitr.Rmd", quiet=TRUE)
+ cat(readLines("knitr.md"), sep="\n")
+ } else {
+ cat(readLines("knitr.Rout.mock", warn = FALSE), sep="\n")
+ }
Loading required package: knitr
Loading required package: data.table
```r
require(data.table) # print?
DT = data.table(x=1:3, y=4:6) # no
DT # yes
```
```
## x y
## 1: 1 4
## 2: 2 5
## 3: 3 6
```
```r
DT[, z := 7:9] # no
print(DT[, z := 10:12]) # yes
```
```
## x y z
## 1: 1 4 10
## 2: 2 5 11
## 3: 3 6 12
```
```r
if (1 < 2) DT[, a := 1L] # no
DT # yes
```
```
## x y z a
## 1: 1 4 10 1
## 2: 2 5 11 1
## 3: 3 6 12 1
```
Some text.
>
>
> proc.time()
user system elapsed
3.116 0.128 3.257
|
