read_ucd

(./IO_Functions/read_ucd.m)

Function Synopsis

ret_struct=read_ucd(inpname);

Help text

READ_UCD read an .inp file, an AVS-Unstructured Cell Data file with
         uniform cell topology of type TRI.

         For an unknown reason, AVS uses the suffix '.inp' to indicate
         a input file for a UCD structure and not the obvious '.ucd', 
         even though the AVS routines which use UCD structures are called 
         UCD routines.  OPNML will adhere to this convention as well.
         This unfortunately conflicts with the filename suffix for
         the FUNDY series of FEM models.

         This routine is provided as an "interface" between the
         AVS-UCD datatype and OPNML/MATLAB in the loosest sense.
         Currently, only the TRANSECT code and the transect routines 
         in QUODDY3.3 and later output a UCD-structure file.
         The .trn (transect) filetype is obsolete.

 Input:   If inpname is omitted, READ_UCD enables a file browser
          with which the user can specify the .inp file.

          Otherwise, READ_UCD takes as input the filename of the 
          transect data file, including the .inp suffix.

 Output:  The output of READ_UCD is a fem_grid_struct containing the
          transect information.  The output structure can be passed
          directly to OPNML routines like COLORMESH2D, LCONTOUR, etc.
          The actual data for the transect is attached to the structure 
          in the field .data.  This .data field  is as wide
          as the number of columns in the node-data specification
          part of the .inp file.  Vector components will be returned
          as three scalars, NOT 1 vector. 

          Read the "man" page for TRANSECT (type "man transect" at a UNIX
          prompt) for more information on the transect output formats.

          Make sure a semi-colon is used at the end of the command; 
          otherwise READ_UCD will return the output arrays to the screen.

          Since OPNML/MATLAB routines are based on linear triangular
          finite elements in 2-D, READ_UCD only reads UCD structures 
          with cell-topologies of type TRI.  No other cell-types, or 
          mixtures of cell-types, are allowed into OPNML/MATLAB through
          this routine.  THIS CLEARLY DOES NOT APPLY TO AVS.

 Call as: transdata=read_ucd(inpname);         

 Written by : Brian O. Blanton (Jun 98)