R: Settings and functions to extend the knitr Stata engine.

Statamarkdown-package {Statamarkdown}

R Documentation

Settings and functions to extend the knitr Stata engine.

Description

To use these functions and settings, attach the Statamarkdown library from within the document to be knit. A typical preliminary code check in a document would be

    ```{r setup, include=FALSE}
    library(Statamarkdown)
    ```

Using the "Stata" language engine in knitr has a number of limitations. Each Stata code chunk is run as a separate batch file, and source code is part of the output returned to the document being knit. This package provides a language engine with code chunk options to overcome these limitations.

If you render multiple documents from the same script or R session, you should detach("Statamarkdown") in between documents.

Code Block (Chunk) Options

Statamarkdown Chunk Options

collectcode: (logical)

A function here sets up a chunk hook, that silently repeats selected code chunks at the beginning of later code chunks. This allows the code in one chunk to use the results of a previous chunk. The user marks code chunks to be silently repeated with the chunk option collectcode=TRUE.

cleanlog: (logical)

A second function here sets up an output hook. This removes Stata code from the output by default. To leave Stata commands in the output, specify the chunk option cleanlog=FALSE.

savedo: (logical)

To save the code from a code block (as a "do" file) and also to save the Stata log file produced by that code block, specify chunk option savedo=TRUE. The filenames are the same as the chunk label.

Knitr Chunk Options

eval: (logical)

Whether or not to evaluate the code in the code block. Use eval=FALSE to show code to the reader without having it evaluated.

Selective evaluation by specifying a numeric vector (an option for R code blocks) does not work for Stata.

include: (logical)

Whether or not any trace of this code block appears in your document. Use include=FALSE to evaluate code but suppress the source code echo and all output (including error messages).

This is equivalent to eval=TRUE, echo=FALSE, results="hide", error=FALSE.

echo: (logical, numeric vector)

Whether or not to show the reader the source code. Use echo=FALSE to suppress the source code in your document.

If this is specified as a numeric vector, it indicates which source lines to show or suppress. For example, echo=c(1,2) shows only the first two lines of the code block in the document (while still evaluating the entire code block). Likewise, echo=-1 hides just the first line of code from the reader.

results: (character)

To suppress normal output while still showing error messages use results="hide".

error: (logical)

Whether or not to show error messages in your document. To suppress error messages use error=FALSE.

Error messages that Stata writes to the log will appear as normal output - they are not "errors" in this context. This option affects error messages returned to/by the operating system.

comment: (character)

A prefix to use before lines of output. The default for R output is comment="##"

child: (character)

Filename to be run and input in the document.

Author(s)

Doug Hemken

References

More documentation and examples: https://www.ssc.wisc.edu/~hemken/Stataworkshops/stata.html#stata-and-r-markdown