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r-exams

Using two templates with custom name in exams2pdf

I am using exams2pdf() to generate two PDF files as:

exams2pdf(file = "ICvar.Rmd",
          name = "icvar",
          engine = "knitr",
          verbose = FALSE, 
          texdir = "tmptex",
          template = c("exam", "solution")
)

But I get this error:

Error in base::file(out_tex[j], open = "w+", encoding = encoding) : invalid 'description' argument

Any ideas why?

Also, is it possible to use custom templates in exams2nops() like template = c("exam", "solution") to produce two PDF files, the first with the questions; the second with the solutions? I read the vignette but could not find any information and adding template to options in exams2nops() does nothing.

Solution

  • The problem is that you only provide a single name = "icvar" but actually need two distinct names for template = "exam" and template = "solution", respectively. Hence, lacking a second name lead to the somewhat cryptic error message. A simple solution is to provide a vector of two name = c("icex", "icsol"), say.

    Additionally, I have just committed a fix to the development version on R-Forge that points this out more clearly in ?exams2pdf, throws an intelligible warning, and provides a workaround. If you use your code above, name is changed to name = c("icvar_exam", "icvar_solution") automatically.

    As for exams2nops(): Internally this essentially sets up a standardized template via make_nops_template() and then calls exams2pdf(). No additional templates can be provided. The reason for this is that all the convenient options in the NOPS template (e.g., adding an intro, selecting the language, switching to twocolumn layout, etc.) would only work for the NOPS template but not the other templates provided. Therefore, if you want to produce a solution sheet you have to use another call to exams2pdf() (or exams2html() or exams2pandoc()) after setting the same random seeds as for exams2nops().