Re: [O] Proposal/request for input: slidify export for html slides

[John Hendy]

On Sat, Feb 8, 2014 at 11:18 AM, Charles Berry <address@hidden> wrote:

>> I still think it makes sense to allow :eval no. This seems more
>> "Org-ish" since the ideology is to have one set of Org syntax where
>> possible, which translates to any number of languages. [...]
>
> In principal, it makes sense to map babel header args to knitr chunk
> options. At least when the headers arg and chunk option do about the
> same thing.
>
> But there is some effort and overhead involved, so only the most
> useful (IMO) have been mapped. Right now, `:noweb yes' will expand the
> reference(s) in place before export, and `:exports none' will not export
> the block. Maybe one day ...

Understood, and no worries. I'm making progress. When you say "expand
references," I'm not sure I follow what that means. References =
references to variables? So something like :var something=something?


> More a matter of what my workflow is (so the issue doesn't arise). I use
> the cache=TRUE chunk option on the knitr side to save the results of long
> running computations. When I start work, I execute a src block that loads
> knitr and knits the *.Rnw (or *.Rmd, etc), which has the side effect of
> loading the cached objects. Then I edit the *.org document. If I am
> working on R code, I run the code interactively either from the src edit
> buffer or I C-c C-c the src block. Its handy to leave the results in the
> *.org buffer for reference - they get stripped on export. Maybe I edit
> a figure caption (knitr option fig.cap=<R character object>), equations,
> or text. When I am ready to see the formatted doc, I export via ravel,
> knit, and view. The cached objects get rebuilt as needed.

Ah. I think I follow this. If you knit the exported .org -> Rmd file
in the same R session that Org is using, if you change the .org and
re-export to .Rmd, knitr is smart enough not to re-run the code? Is
that what you mean? That also must imply that export to .Rmd doesn't
execute any of the Org babel code, right (otherwise there would be no
benefit to your workflow since you'd be waiting for Org anyway)?

If that's the case, I think I could roll with that -- I'd just have
:eval yes if exporting to .Rmd -> knitr, and do a replace-string to
:eval no if I was going to export to Beamer.

>> My workflow might be odd in that I tend to futz with plot parameters
>> once, get the desired image, and then set :eval no for the rest of my
>> document work so I don't have to wait for plots on iterative exports.
>> I try to put all my setup code (load packages, data
>> reading/manipulation, etc.) in it's own block so that I can easily run
>> that whenever I first open the document. From there I only need to
>> re-run a plot block if necessary and I'll just temporarily change
>> :eval no -> yes and then back again after execution.
>>
>
> Not odd at all if it saves you time.
>
> But if it takes long to rebuild the objects in that first src block, you
> might want to try the cache=TRUE route.

I'm a bit hung up on including non-code-generated images. I'm working
through one of my presentations to convert to slidify (and may write
up a Worg tutorial or just one on my blog to add to collective
knowledge) but am not sure of the right "universal Org syntax" that
will work with multiple backends. I'm most used to something like
this:

#+begin_center
#+attr_backend :height {6cm, 400px, etc.}
[[./path/to/image.png]]
#+end_center

That's not seeming to work with ox-ravel thus far. I'd love not to
have to change the Org image syntax to straight markdown just for my
occasional use of slidify.


Thanks again -- you've been immensely helpful in getting me started!
John

>
>
> Chuck
>
> p.s. the weird fontification you noted one posting up in this thread seems
> like something to raise with the slidify/knitr devs after checking the
> *.Rmd to be sure there is no org/ravel induced problem.
>

Will do, but I'm really thinking it's got to be crud that exported
from my various latex lines/settings. If things persist after making
sure none of that made it through to .Rmd, I'll submit an example file
to either knitr or slidify github issues.

>
>