gdal_contour -inodata / -snodata documentation weak

[jidanni]

Feature description

gdal_contour man page says:

   -inodata
          Ignore any nodata value implied in the dataset - treat all values as valid.

   -snodata <value>
          Input pixel value to treat as "nodata".

So if I did -snodata 0 -inodata that would be a no-op? OK the program should raise an error, and here's the new man page proposal:

   -inodata
          Ignore any nodata value implied in the dataset - treat all values as valid.
          Cannot be used with -snodata.

   -snodata <value>
          Input pixel value to treat as "nodata" and thus ignored.
          Cannot be used with -inodata.

Naturally there's a 50% chance I am not understanding the whole thing, with a 95% chance that it's an underly-clear man page to blame.

Googling only finds https://github.com/OSGeo/gdal/issues/594 .

P.S., Google can't read https://gdal.org/en/latest/programs/gdal_contour.html . Screenshot appended.

How to fix it This isn't my site The page owner prohibited Google from reading the page, which prevents us from creating a page description. Unfortunately there's nothing that Google can do about this. If you know the site owners, tell them about it, and send them a link to this page.

P.P.S., trailing blanks spotted:

$ gdal_contour --long-usage | wc -l
38
$ gdal_contour --long-usage | grep ' $' | wc -l
20

Screenshots

Maybe the idea was to direct the user to the stable version instead of latest.

Well the result looks like some closed source project or something.