                    README FILE FOR CHAPTER-1 PROGRAMS
                    ----------------------------------

1.  fsigma.c
        This program calculates the material stress fringe value by using
        least squares technique.
    User input : data file (fsigma.dat) having load, radius, magnification 
                 and fringe order at (x,y) position.
    Output     : material fringe value. 

2.  reconstr.c
        This program generates the theoretical fringe patterns for disc under
    diameteral compression. 
    
    User input 
        disk radius                     (30.0)
        dosk load                       (1350.0)
        material fringe value(fsigma)   (13.3878)
        thickness                       (6.25)
        magnification                   (2.3)
        choice of symmetry              (1)
        bright or dark field choice     (b or d)
        scanwidth_x                     (1)
        scanwidth_y                     (1)
        fringe width                    (0.2)
        choice for echo data point      (y)
        Enter the echo data file name

    note - 1. to run this program egavga.bgi file is required in the current 
              directory which is used to initialise the VGA display in graphics 
              mode.
           2. for echo data file open the fsigma.dat and delete the first 
              three data and write the number of data point (40)
