The rid filter is useful for removing empty lines in Humdrum data. A primary use of the filter is in clean-up of spacer lines in the data after a part has been extracted.
Removing null lines
The options -g, -l, -i, and -d are useful for removing empty
global comments (!!), local comments (!), interpretations (*) and
data lines (.).
See also
See the Humdrum Toolkit documentation for the rid tool, which is mostly compatible with the VHV filter implementation of rid.
See the Humdrum Extras documentation for the ridx tool, which is nearly identical to the VHV filter implementation of rid.