root/bdm/stat/libFN.h @ 19

//
// C++ Interface: itpp_ext
//
// Description:
//
//
// Author: smidl <smidl@utia.cas.cz>, (C) 2008
//
// Copyright: See COPYING file that comes with this distribution
//
//
#include <itpp/itbase.h>
#include "libBM.h"

using namespace itpp;

//! class representing function $f(x) = a$, here rv is empty
class constfn : public fnc
{
                RV rv;
                vec val;

        public:
                vec eval() {return val;};
                vec eval ( vec &cond ) {return val;};
                //!Default constructor
                constfn ( const vec &val0 ) :rv(),val ( val0 ) {};
};

//! Class representing function $f(x) = Ax+B$
class linfn: public fnc
{
                RV rv;
                ivec indexlist; // needed by evalsome
                mat A;
                vec B;
        public :
                vec eval ( vec &cond ) {it_assert_debug ( cond.length() ==rv.count(), "linfn::eval Wrong cond." );return A*cond+B;};

                linfn evalsome ( ivec &rvind );
                linfn ( const RV &rv0 ) :rv ( rv0 ),A ( eye ( rv0.count() ) ),B ( zeros ( rv0.count() ) ) { indexlist=rv.indexlist();};
                linfn ( const RV &rv0, const mat &A0 ) : rv ( rv0 ), A ( A0 ), B ( zeros ( rv0.count() ) ) { indexlist=rv.indexlist();};
                linfn ( const RV &rv0, const mat &A0, const vec &B0 ) :rv ( rv0 ), A ( A0 ), B ( B0 ) { indexlist=rv.indexlist();};
};

//! Class representing function $f(x,u) = Ax+Bu$
class bilinfn: public fnc
{
                RV rv;
                ivec indexlist; // needed by evalsome
                mat A;
                mat B;
        public :
                vec eval ( vec &cond )
                {
                        it_assert_debug ( cond.length() ==rv.count(), "linfn::eval Wrong cond." );
                        int sizex = A.cols();
                        return A*cond(0,sizex-1)+B*cond(sizex,-1);//-1 = end (in matlab)
                };
                vec eval ( vec &xcond, vec &ucond )
                {
                        it_assert_debug ( xcond.length() ==rv.count(), "linfn::eval Wrong cond." );
                        return A*xcond+B*ucond;
                };

                bilinfn evalsome ( ivec &rvind );
                bilinfn ( const RV &x0, const RV &u0 ) :A ( eye ( x0.count() ) ),B ( zeros ( x0.count(),u0.count() ) )
                {
                        rv=x0; rv.add ( u0 );
                        indexlist=rv.indexlist();
                };
                bilinfn ( const RV &x0, const RV &u0, const mat &A0, const mat &B0 );
};