[knitr] Language engines: Use other languages in knitr | /knitr/demo/engines/

Currently the support of syntax highlighting for LaTeX and HTML is poor, and there is no support to graphics for Python. I may add them in future versions, but I'm really weak at Python, so I do not know when this can be done.

Originally posted on 2012-10-02 15:55:15

Guest *David Forrest* @ 2012-10-26 19:50:15 originally posted:

 Wouldn't one solution be to write the python code to explicitly create a
figure, then explicitly reference that figure in the markup?

Of course it can be done that way; it is just a little bit inelegant to manually save figures. Perhaps I'm spoiled by R, in which I can automatically save and insert plots.

Originally posted on 2012-10-26 20:40:29

Guest *zhanxw* @ 2013-10-17 04:11:34 originally posted:

Will this library make things easier?
https://code.google.com/p/google-code-prettify/

Thanks, but that is only for web pages. The latest version of knitr actually supports syntax highlighting for Python now (works for both LaTeX and HTML).

Originally posted on 2013-10-21 03:51:23

Guest *CJ* @ 2014-03-06 10:33:15 originally posted:

why you don't put Latex as a language engine... that's easy to use pygments to highlight it if you do this.

Yes it is possible. You can simply purl('bash.Rmd', output = 'test-bash.bash') inside bash.Rmd.

Originally posted on 2012-10-26 20:37:28

Guest *David Forrest* @ 2012-10-26 21:29:41 originally posted:

 Thanks,

That looks like it grabs all the code into one file.  How would that work for just one chunk or set of chunks?

I guess I'm looking for something like the chunk-specifc feature of notangle:

For an Rnw file I found I can do this to strip out the options and selectively tangle:

sed '/<>/>>/' testAll.Rnw | notangle -Rtest-bash > test-bash.bash

It is easy to implement (should be one liner) by introducing a new chunk option like tangle=TRUE/FALSE. I just have not decided whether to do it.

Originally posted on 2012-10-27 05:07:49

Guest *David Forrest* @ 2012-10-30 20:38:33 originally posted:

Without modifying knitr,  here's an R function to call a notangle command on a noweb or sweave/knitr .Rnw file:

 notangle<-function(file=NULL,root='*',output=NULL){
 # Clean chunk options from an Sweave/knitr file and run notangle on the result with -R to output or stdout
 # assume notangle is on the system path
   if  (is.null(file))
     stop("file not set, exiting")
   commandLine<-sprintf("sed '/^<>/>>/' %s | notangle -R%s",file,root)
   if (! is.null(output))
     commandLine = paste(commandLine, output,sep=" > ")
   system(commandLine)
 }

It might be nice to add a root='*' default option to purl() and treat it like a regex on the chunknames like the -R option of notangle. 

If noweb's notangle took a regex as a -R root, then it could operate on knitr or sweave files directly.   Short of that, one can use a filter like the above to make .Rnw files compatible with noweb.

Hi, please make sure the path to sas.exe is correct. I think you copied it from my example, but that does not guarantee you installed SAS to the same directory.

The better approach is to set your PATH to contain the path of sas.exe, so you do not need to use engine.path at all. To know more about PATH, see http://www.computerhope.com/issues/ch000549.htm

Originally posted on 2013-07-11 05:43:59

Guest *Paul Hurtado* @ 2015-12-15 22:38:19 originally posted:

I have a similar problem trying to use knitr to run python code in Windows 7 (through TeXstudio, not Rstudio). PATH is set correctly (I can run python.exe from the command prompt) but it acts like it can't find python (doesn't run) unless I specify engine.path=... Also, it keeps giving an error saying I need to install highlight, which was installed and added to PATH (and runs from the command prompt when I type "highlight").

Could your code need to make use of normalizePath() somewhere perhaps?

Guest *skohari* @ 2016-01-08 21:39:46 originally posted:

Xiuting Mi,

Since you're generating a null dataset, %put will put' the Hello world statement to the log, not to the result window; hence there is nothing generated in the html file. I'd suggest running some other simple code like proc freq` etc. to see the results. Check out this brilliant piece http://www.ssc.wisc.edu/～hemken/SASworkshops/SASWindows/Markdown/SASmarkdown.html

Unfortunately no, that is not possible at the moment. You may file a feature request to support.rstudio.com if you want.

Originally posted on 2015-12-09 23:29:12

{python3} is not supported yet, but you can set engine.path='python3' in {python}.

Originally posted on 2016-09-10 03:27:04

Experiment here: https://github.com/yihui/runr

Originally posted on 2016-11-01 19:15:59

Please see yihui/knitr#1350

Originally posted on 2017-03-06 19:41:46

Guest *Ben Bolker* @ 2017-07-17 00:35:51 originally posted:

there is via the runr package: see https://rpubs.com/yihui/julia-knitr (you'll have to install runr from Github. I'm finding the socket-based version flaky and will probably fall back to doing it as e.g. via Python ("julia -E" might do the trick?)