DEFINITION MODULE AmoebaM;

  (* EXPORT QUALIFIED Amoeba; *)

   FROM NRMath IMPORT VectorFunction;
   FROM NRVect IMPORT Vector;
   FROM NRMatr IMPORT Matrix;

   PROCEDURE Amoeba(    P:     Matrix;
                        Y:     Vector;
                        ndim:  INTEGER;
                        ftol:  REAL; 
                        func:  VectorFunction;
                    VAR nfunc: INTEGER); 
   (*
     Multidimensional minimization of the function func(x)
     where x[ndim] is a vector in ndim dimensions, by the downhill
     simplex method of Nelder and Mead.  The matrix P[ndim+1][ndim]
     is input. Its ndim+1 rows are ndim-dimensional vectors which are the
     vertices of the starting simplex.
     Also input is the vector Y[ndim+1], whose components must be pre-
     initialized to the values of func evaluated at the ndim+1 vertices (rows) 
     of P; and ftol the fractional convergence tolerance to be achieved in the
     function value (n.b.!).  On output, P and Y will have been reset to ndim+1
     new points all within ftol of a minimum function value, and nfunc gives 
     the number of function evaluations taken.
   *)

END AmoebaM.