help Rec1980
  ABAQUS modal output to MATLAB
  
  Syntax
      #Rec# = Fil2str('*.fil');
      #out# = Rec1980(#Rec#)
 
  Description
      Read modal output from the results (*.fil) file generated from the
      ABAQUS finite element software. The asterisk (*) is replaced by the
      name of the results file. The record key for modal output is 1980 (in
      ABAQUS/Standard) and is written once per eigenvalue in a natural
      frequency extraction step. See section "Results file output format"
      in ABAQUS Analysis User's manual for more details.
      The following options with parameters have to be specified in the
      ABAQUS input file for the results (*.fil) file to be created and
      contain frequency analysis results (#n# is the number of requested
      eigenvalues):
          ...
          *FREQUENCY
          #n#
          *FILE FORMAT, ASCII
          ...
      NOTE: The results file (*.fil) must be placed in the same directory
      with the MATLAB source files in order to be processed.
      
  Input parameters
      #Rec# (string) is an one-row string containing the ASCII code of the
          ABAQUS results (*.fil) file. It is generated by the function
          Fil2str.m.
  
  Output parameters
      #out# ([#n# x 16]) is a double array containing the attributes of the
          record key 1980 as follows:
          Column  1  –  Eigenvalue number. 
          Column  2  –  Eigenvalue. 
          Column  3  –  Generalized mass. 
          Column  4  –  Composite damping. 
          Column  5  –  Participation factor for degree of freedom 1. 
          Column  6  –  Effective mass for degree of freedom 1. 
          Column  7  –  Participation factor for degree of freedom 2. 
          Column  8  –  Effective mass for degree of freedom 2. 
          Column  9  –  Participation factor for degree of freedom 3. 
          Column 10  –  Effective mass for degree of freedom 3. 
          Column 11  –  Participation factor for degree of freedom 4. 
          Column 12  –  Effective mass for degree of freedom 4. 
          Column 13  –  Participation factor for degree of freedom 5. 
          Column 14  –  Effective mass for degree of freedom 5. 
          Column 15  –  Participation factor for degree of freedom 6. 
          Column 16  –  Effective mass for degree of freedom 6. 
          where #n# is the number of requested eigenvalues in the frequency
          extraction step. If the results file does not contain the desired
          output, #out# will be an empty array
 
  _________________________________________________________________________
  Copyright (c) 2016
      George Papazafeiropoulos
      Captain, Infrastructure Engineer, Hellenic Air Force
      Civil Engineer, M.Sc., Ph.D. candidate, NTUA
      Email: gpapazafeiropoulos@yahoo.gr
      Website: http://users.ntua.gr/gpapazaf/