001412L   0600049   22040000150000012815DQLC49430000;&RR01DQLC0100;&DDF RECORD IDENTIFIER1600;&LOGICAL CONSISTENCYMODN!RCID!COMT(A,I,A)01079 R     00043   4104000100070DQLC10297     1DQLC     1DLG-3 Topo  Topological requirements include the following: lines must begin and end at nodes, lines must connect to each other at nodes, lines do not extend through nodes, left and right areas are defined for each line element and are consistent throughout the file, and lines representing the limits of the file (neatline) are free of gaps.  The tests of logical consistency were performed by USGS processing software.  The neatline was generated by connecting the four corners of the digital file, as established during initialization of the digital file.  All data outside the enclosed region were ignored and all data crossing these geographically straight lines were clipped at the neatline.  Data within a specified tolerance of the neatline were snapped to the neatline.  Neatline straightening aligned the digitized edges of the digital data with the generated neatline; that is, with the longitude/latitude lines in geographic coordinates.  All internal areas were tested for closure using USGS software.  