{ Copyright (C) 1986 Adam Fritz, 133 Main St., Afton, N.Y. 13730 }

program PRDR ;
     {                                                     }
     { PROGRAM:                                            }
     {                                                     }
     {    Pan-Reif driver.                                 }
     {                                                     }
     { VERSION:                  DATE:                     }
     {                                                     }
     {    TURBO Pascal 1.1          April 25, 1986         }
     {                                                     }
     { DESCRIPTION:                                        }
     {                                                     }
     {    Initialize                                       }
     {       Get control parameters                        }
     {    Generate and display test matrix                 }
     {    Compute and display inverse matrix               }
     {    Compute and display residuals                    }
     {                                                     }
     { AUTHOR:                                             }
     {                                                     }
     {    Adam Fritz (TURBO Pascal)                        }
     {                                                     }

const
     lda            = 10 ;
     iterxx         = 100 ;

type
     MATRIX         = array[1..lda,1..lda] of real ;
     VECTOR         = array[1..lda] of real ;

     RowPointer     = ^Row ;
     Row            = record
                         s : VECTOR
                      end ;

var
     n              : integer ; { dimension }
     iterx          : integer ; { maximum number of iterations }
     residx         : real ;    { convergence control }
     a              : MATRIX ;  { matrix to invert }
     b              : MATRIX ;  { approximate inverse }
     r              : MATRIX ;  { residual matrix }
     x              : MATRIX ;  { working matrix }

     i,j            : integer ; { loop indices }

{~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~}

{$I HilGen.pas                  Hilbert test matrix generator   }
{-$I RanGen.pas                  Random test matrix generator    }

{$I BLAS.pas                    Basic Linear Algebra routines  }
{$I PR.pas                      Pan-Reif procedure              }

{$I OUT.pas                     Formatted output routine      }

{~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~}

procedure Initialize ;

begin
                                { get control parameters }
   repeat
      Write ('Dimension = ') ;
      Readln (n)
   until ((n > 0) and (n <= lda)) ;
   repeat
      Write ('Iterations = ') ;
      Readln (iterx)
   until ((iterx > 0) and (iterx <= iterxx)) ;
   repeat
      Write ('Residual = ') ;
      Readln (residx)
   until (residx > 0.0)

end ;

{~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~}

begin

   writeln ('Pan-Reif Test Program.') ;
   writeln ;
                                { initialize }
   Initialize ;
                                { compute and display test matrix }
   MatGen (a,lda,n) ;
   writeln ;
   writeln ('Original Matrix (by column):') ;
   writeln ;
   OUT (a[1,1],lda,n,n) ;
                                { compute and display inverse }
   PanReif (a,b,r,x,lda,n,iterx,residx) ;
   writeln ('Iterations: ',iterx:3) ;
   writeln ;
   writeln ('Inverse (by column):') ;
   writeln ;
   OUT (b[1,1],lda,n,n) ;
                                { Display Residuals }
   writeln('Residuals (by column):') ;
   writeln ;
   OUT(r[1,1],lda,n,n) ;

   writeln ('End of Test.')

end.

{ Copyright (C) 1986 Adam Fritz, 133 Main St., Afton, N.Y. 13730 }