Save Rscript in Rmd format - r

Question

I have R script.
mydat=read.csv("C:/Users/Admin/Downloads/test.csv", sep=";",dec=",")
View(mydat)
str(mydat)
#deleted after FS
mydat$symboling.<-NULL
mydat$make.<-NULL
mydat$num.of.cylinders.<-NULL
mydat$fuel.type.<-NULL
mydat$aspiration.<-NULL
mydat$num.of.cylinders.<-NULL
#this vars have small num. of obs.
mydat$engine.type.<-NULL
mydat$engine.location.<-NULL
mydat$num.of.doors.<-NULL
mydat=na.omit(mydat)
#Feature Selection
FS=Boruta(normalized.losses.~.,data=mydat)
getSelectedAttributes(FS, withTentative = F)
plot(FS, cex.axis=0.5)
#get scatterplot
scatter.smooth(x=mydat$length.,y=mydat$normalized.losses.,main="normalized losse~length")
#split sample on train and sample
index <- sample(1:nrow(mydat),round(0.70*nrow(mydat)))
train <- mydat[index,]
test <- mydat[-index,]
I have to save it in Rmarkdown format (html).
Of course in Rstudio i can do that:
file-new file-rmarkdown-HTML
and i get this script
```{r cars}
summary(cars)
```
I don't want manually write this prefix ```{r}.
Is it possible to make that those parts of the code that are separated by comments
#
#
were saved in rmarkdown format?
In output i expect for example
```{r}
mydat$symboling.<-NULL
mydat$make.<-NULL
mydat$num.of.cylinders.<-NULL
mydat$fuel.type.<-NULL
mydat$aspiration.<-NULL
mydat$num.of.cylinders.<-NULL
```

Answer 1

You can use the spin() function from the knitr package.
It will produce an .md file (but you can keep the intermediate .Rmd with the precious = TRUE argument), using the '#' chracter as the 'documentation argument:
doc
A regular expression to identify the documentation lines; by default it follows the roxygen convention, but it can be customized, e.g. if you want to use ## to denote documentation, you can use '^##\s*'.
For example:
spin('test.R', precious = TRUE, doc = '#')
produces:
test.Rmd
```{r }
mydat=read.csv("C:/Users/Admin/Downloads/test.csv", sep=";",dec=",")
View(mydat)
str(mydat)
```
deleted after FS
```{r }
mydat$symboling.<-NULL
mydat$make.<-NULL
mydat$num.of.cylinders.<-NULL
mydat$fuel.type.<-NULL
mydat$aspiration.<-NULL
mydat$num.of.cylinders.<-NULL
```
this vars have small num. of obs.
...
test.md
```r
mydat=read.csv("C:/Users/Admin/Downloads/test.csv", sep=";",dec=",")
```
```
## Warning in file(file, "rt"): cannot open file 'C:/Users/Admin/Downloads/
## test.csv': No such file or directory
```
```
## Error in file(file, "rt"): cannot open the connection
```
```r
View(mydat)
```
...
You may also have a look at the stitch() function and sibilings (stitch_rhtml and stitch_rmd), have a look here