I'm afraid I can't follow your explanation
When I open a file, I find many-many lines that start with "g wall_xx_xx" where xx_xx are numbers. In that particular file the first "g wall" is preceded by 44 lines that start with "f". I assume those are the faces of the walls I have drawn at the start of the project.
All the other occurences of "g wall" are preceded by only 2 lines that start with "f".
So, how can I determine which f-lines to delete?
Should there be one (and one only) wall that starts with "g wall" and has no numbers following?
I don't have the patience to use the trial-and-error method and delete each (pair of) f-line(s) to find out which line is the unwanted floor. Sorry for that.
Hans