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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.
|
