# Copyright (c) P.J.Gawthrop 1991, 1992, 1994.

###############################################################
## Version control history
###############################################################
## $Id$
## $Log$
## Revision 1.5  1998/05/20 15:23:26  peterg
## Put MTTYz := MTTYz outsise the BEGIN/END
##
## Revision 1.4  1998/05/20 15:13:09  peterg
## Writes out algebraic equations (if any).
##
## Revision 1.3  1998/03/03 09:02:46  peterg
## Replaced MTTEyx*MTTEdX + MTTEyu*MTTdu; term
##
## Revision 1.2  1997/08/26 08:22:36  peterg

## Sorted out bug when MTTNz=0
##
## Revision 1.1  1996/08/15 16:47:02  peter
## Initial revision
##
###############################################################


#Explicit solution option
Solving=$2;
if [ "$Solving" = "Solving" ]; then
    solve=1
    echo "Creating $1_cse.r (with explicit solution of algebraic equations)"
else
    solve=0
    echo "Creating $1_cse.r"
fi

# Remove the old log file
rm -f dae2cse_r.log

# Use reduce to accomplish the transformation
$SYMBOLIC >dae2cse_r.log << EOF

OFF Echo;
OFF Nat;
ON NERO;

in "$1_def.r";
MTTdxs := MTTdX;  %Save the symbolic form of dX

in "$1_subs.r";
in "$1_dae.r";


%Create F_x, F_y matrices - assumming equations are 
% linear in dZ
IF MTTNz>0 THEN 
BEGIN
% Find MTTFx;
write "% Find MTTFx;";

matrix MTTFx(MTTNx,MTTNz);
FOR j := 1:MTTNz DO

  MTTdZ17 := 0;
  MTTdZ18 := 0;
  MTTdZ19 := 0;

MTTEdX := MTTdX; %Ie MTTEdX is MTTdX with the dz terms deleted ie EdX.
MTTdX := MTTdXs;  %Restore the symbolic dX

%% Add on input derivative terms
MTTEdX := MTTEdX + MTTExu*MTTdu;


MTTY := MTTY + MTTEyx*MTTEdX;
%%% This causes the matrix mismatch
%%% MTTdXs and MTTdu need setting in _def.r file
%%MTTY := MTTY +  MTTEyu*MTTdu;
MTTY := MTTY + MTTEyx*(MTTE^(-1))*MTTEdX;





END; %%of MTTNz>0

IF MTTNz=0 THEN 
BEGIN
  MTTEdX := MTTdX;
  MTTE   := MTTI;
END;

IF (MTTNyz>0) AND ($solve>0) THEN
BEGIN
  %%%% Try and solve algebraic loops!!

  %Create list of the relevant equations 
  MTT_eqns := {};
  FOR i := 1:MTTNyz DO
    MTT_eqns := append(MTT_eqns,{MTTyz(i,1)});

  %Create list of the relevant unknowns
  MTT_unknowns := {};
  FOR i := 1:MTTNyz DO
    MTT_unknowns := append(MTT_unknowns,{MTTUi(i,1)});

  %Solve the algebraic equations symbolically
  %The result seems to be in an extra list - I don't know why
  % So remove the outer list with first.

  MTT_sol := first(solve(MTT_eqns,MTT_unknowns));

  %Substitute back into the equations
  FOR i := 1:MTTNyz DO
  BEGIN
    MTT_sol_i := first(MTT_sol); MTT_sol := rest(MTT_sol);
    set(lhs(MTT_sol_i),rhs(MTT_sol_i));
  END;

  % No algebraic variables left!
  MTTNYz := 0;
END; % IF MTTNyz>0

%%Create the _cse.r file
OUT "$1_cse.r";

IF MTTNx>0 THEN
BEGIN
  write "matrix MTTEdX(", MTTNx, ",1)";
END;
MTTEdX := MTTEdX;

IF MTTNy>0 THEN
BEGIN
  write "matrix MTTY(", MTTNy, ",1)";
END;

MTTY := MTTY;

IF MTTNu>0 THEN
BEGIN
  write "matrix MTTU(", MTTNu, ",1)";
  write "matrix MTTdU(", MTTNu, ",1)";
END;

  MTTEyx := MTTEyx;
%%%%%  MTTdU := MTTdU;
END;

IF MTTNyz>0 THEN
  BEGIN
  write "matrix MTTYz(", MTTNyz, ",1)";
  END
ELSE
  BEGIN
  write "MTTNYz := 0;";
  MTTYz := 0;
  END;

  MTTYz := MTTYz;


write ";END;";

SHUT "$1_cse.r";
quit;

EOF

# Now invoke the standard error handling.
mtt_error_r dae2cse_r.log