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rcaptiontext-formattingofficer

How to put a subscript in a caption of a Word document using officer in R

I am trying to add a subscript to a caption generated in officer. I am creating the caption like this:

library(officer)

doc <- read_docx('empty_file.docx')

autonum <- run_autonum(seq_id = 'fig', pre_label = 'Figure ')
caption <- block_caption(label='My caption includes SO2.', style = "caption", autonum = autonum)
doc <- body_add_caption(doc, caption)

print(doc, target = 'output.docx'))

However, now I'd like to put the '2' in 'SO2' in subscript. I know how to generate subscripts:

fp_text_prop <- fp_text(color='orange')
prop_mod <- update(fp_text_prop, vertical.align = 'subscript')
paragraph <- fpar(ftext('SO', prop = fp_text_prop), ftext('2', prop = prop_mod)))

But I can't use the resulting fpar inside a caption, as body_add_caption expects the output from block_caption and block_caption expects a normal string as argument for the label=.

How can I put an fpar, or alternatively, a subscript inside a caption?

Solution

  • I have found a solution that is a bit involved but seems to work.

    library(officer)

doc <- read_docx('empty_file.docx')

autonum <- run_autonum(seq_id = 'fig', pre_label = 'Figure ')

fp_text_prop <- fp_text(color='orange')
prop_mod <- update(fp_text_prop, vertical.align = 'subscript')

caption <- fpar(autonum, ftext('SO', prop = fp_text_prop), ftext('2', prop = prop_mod)))

doc <- body_add_fpar(x=doc, value=caption, style = 'caption')

print(doc, target = 'output.docx'))

    There are a couple of caveats: fp_text_prop should match the normal style of the captions and style = 'caption' should be changed to pick the correct style for captions in your document.