Error: NDP divide by zero

Solution or Workaround


When running the AMATCH command, this error message occurs:

NDP divide by zero (see section B.2 in F77L manual) in MATPNT
Called by AMATCH
Called by MAIN


The coverage's topology needs to be updated prior to running the AMATCH command.


Run the CLEAN command on the coverage prior to performing any of these commands: ACREATE, ABUILD, and AMATCH.

If a CLEAN is performed, and subsequent new topological relationships are established in the .AAT file, that is CLEAN forced intersections at arcs that did not have prior nodes, then the coverage will need to be manually edited in ARCEDIT to fix the duplicate arc problem. Duplicate arcs can be identified using the FREQUENCY command on the item cover_ID.