Sub-Area Extraction

I tried two methods to do a sub-area extraction based on what I could find in cube help:

  • Method 1 was using the following statements in the highway assignment program: FILEO SUBAREAMATO, FILEI SUBAREANETI, and SUBAREAMAT[] in the ILOOP
  • Method 2 was by using FILEO PATHO, and using the PATHO (along with PATHOGROUP, and FULLPATH) statements in the ILOOP to generate a PATH file and then using the Sub-Area Extraction polygon tool.

Is one of these methods preferred? I noticed that the assignment volumes that resulted from method 1 were identical to the parent network while those from method 2 were slightly off.