When I use readcell() to import a .xlsx file, any empty cells are stored as 1x1 missing. Then if I try to write the cell array back to a .csv file using writecell(), I get an error that missing values aren't allowed. It seems strange to me that readcell() would create something that writecell() can't handle, but given this limitation, how can I automatically detect all cells in my cell array that are missing and replace them with an empty string? I tried ismissing() and fillmissing() but these didn't work.
r = readcell('myinput.xlsx')
fillmissing(r, 'constant', '')