knitr已更新，实际版本为1.15.1，支持更多引擎：八度音就是其中之一：

library(knitr)
names(knit_engines$get())

 [1] "awk"       "bash"      "coffee"    "gawk"      "groovy"   
 [6] "haskell"   "lein"      "mysql"     "node"      "octave"   
[11] "perl"      "psql"      "python"    "Rscript"   "ruby"     
[16] "sas"       "scala"     "sed"       "sh"        "stata"    
[21] "zsh"       "highlight" "Rcpp"      "tikz"      "dot"      
[26] "c"         "fortran"   "fortran95" "asy"       "cat"      
[31] "asis"      "stan"      "block"     "block2"    "js"       
[36] "css"       "sql"

要在Rmarkdown笔记本中添加八度音阶代码，请用途：

```{octave}
# Insert your octave code here

knitr目前支持的引擎有

> require(knitr);
names(knit_engines$get())
 [1] "awk"       "bash"      "coffee"    "gawk"      "haskell"   "perl"      "python"    "Rscript"    "ruby"      "sas"      
[11] "sed"       "sh"        "zsh"       "highlight" "Rcpp"      "tikz"      "dot"       "c"         "asy"       "cat"

因此，是的，matlab目前不支持作为knitr引擎，但这（Convert MATLAB code to R）可能有助于将matlab代码移植到R