/*===========================================================================
 
 Copyright (C) 2007-2012 Yves Renard, Julien Pommier.
 
 This file is a part of GETFEM++
 
 Getfem++  is  free software;  you  can  redistribute  it  and/or modify it
 under  the  terms  of the  GNU  Lesser General Public License as published
 by  the  Free Software Foundation;  either version 3 of the License,  or
 (at your option) any later version along with the GCC Runtime Library
 Exception either version 3.1 or (at your option) any later version.
 This program  is  distributed  in  the  hope  that it will be useful,  but
 WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 or  FITNESS  FOR  A PARTICULAR PURPOSE.  See the GNU Lesser General Public
 License and GCC Runtime Library Exception for more details.
 You  should  have received a copy of the GNU Lesser General Public License
 along  with  this program;  if not, write to the Free Software Foundation,
 Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301, USA.
 
===========================================================================*/
#include <getfem/getfem_assembling.h>
#include <getfem/getfem_assembling.h>
#include <getfem/getfem_export.h>
#include <getfem/getfem_regular_meshes.h>
#include <getfem/getfem_mat_elem.h>
#include <gmm/gmm.h>
#ifdef GETFEM_HAVE_SYS_TIMES
# include <sys/times.h>
#endif
#include <unistd.h>

using std::endl; using std::cout; using std::cerr;
using std::ends; using std::cin;

using bgeot::base_vector;
using bgeot::base_matrix;
using bgeot::base_small_vector;
using bgeot::base_node;
using bgeot::scalar_type;
using bgeot::size_type;
using bgeot::short_type;
using bgeot::dim_type;

typedef gmm::wsvector<scalar_type> sparse_vector_type;
typedef gmm::row_matrix<sparse_vector_type> sparse_matrix_type;
typedef std::vector<scalar_type> linalg_vector;


using std::flush;
#define flushy flush

int fail_cnt = 0;

void classical_mesh_fem(getfem::mesh_fem& mf, getfem::short_type K) {
  for (dal::bv_visitor cv(mf.linked_mesh().convex_index()); !cv.finished();
       ++cv) {
    bgeot::pgeometric_trans pgt = mf.linked_mesh().trans_of_convex(cv);
    mf.set_finite_element(cv, getfem::classical_fem(pgt,K));
  }
  //mf.set_classical_finite_element(K,2*K);
}
#define ASSEMBLY_CHECK

#ifdef ASSEMBLY_CHECK

typedef enum {DO_BOUNDARY_MASS,
      DO_SCAL_VOLUMIC_SOURCE,
      DO_VEC_VOLUMIC_SOURCE,
      DO_SCAL_MASS_MATRIX,
      DO_VEC_MASS_MATRIX,
      DO_SCAL_LAPLACIAN,
      DO_SCAL_L2_NORM,
      DO_VECT_H1_NORM,
      DO_LIN_ELAST, 
      NB_TESTS} t_do_what;

#ifdef HAVE_SYS_TIMES
struct chrono {
  struct ::tms t;
  ::clock_t t_elapsed;
  float cpu_, elapsed_, system_;
  float nbclocktk;
public:
  chrono() { nbclocktk = ::sysconf(_SC_CLK_TCK); }
  void init() { elapsed_=0; cpu_=0; system_ =0; }
  void tic() { t_elapsed = ::times(&t); }
  void toc() { 
    struct tms t2; ::clock_t t2_elapsed = ::times(&t2); 
    elapsed_ += (t2_elapsed - t_elapsed) / nbclocktk;
    cpu_     += (t2.tms_utime - t.tms_utime) / nbclocktk;
    system_  += (t2.tms_stime - t.tms_stime) / nbclocktk;
    memcpy(&t, &t2, sizeof(struct tms));
  }
  float cpu() const { return cpu_; }
  float elapsed() const { return elapsed_; }
  float system() const { return system_; }
};
#else
struct chrono {
  float t,cpu_;
public:
  chrono() { }
  void init() { cpu_=0; }
  void tic() { t = float(::clock())/float(CLOCKS_PER_SEC); }
  void toc() {
    float t2 = float(::clock())/float(CLOCKS_PER_SEC);
    cpu_ += t2 - t; t = t2;
  }
  float cpu() const { return cpu_; }
  float elapsed() const { return cpu_; }
  float system() const { return 0.; }
};
#endif

std::ostream& operator<<(std::ostream& o, const chrono& c) {
  o << "[elapsed=" << int(c.elapsed()*1000) << "ms, cpu=" << int(c.cpu()*1000) << "ms, system=" << int(c.system()*1000) << "ms]";
  return o;
}

struct g_params {
  ftool::md_param PARAM;

  size_type NX,Ndim;
  int mesh_type;
  int K, K2, Kdata;
  bool do_new, do_old;
  int do_what;
  void init(int argc, char *argv[]);
};

g_params param;

void g_params::init(int argc, char *argv[]) {
  PARAM.add_int_param("NX", 50);
  PARAM.add_int_param("NDIM", 2);
  PARAM.add_int_param("MESH_TYPE", 0);
  PARAM.add_int_param("K", 3);
  PARAM.add_int_param("K2", 3);
  PARAM.add_int_param("KDATA", 1);
  PARAM.add_int_param("BENCH_NEW", 1);
  PARAM.add_int_param("BENCH_OLD", 1);
  PARAM.add_int_param("BENCH_WHAT", -1);

  PARAM.read_command_line(argc, argv);
  NX = PARAM.int_value("NX", "Domaine dimension");
  Ndim = PARAM.int_value("NDIM", "Number of dimensions");
  mesh_type = int(PARAM.int_value("MESH_TYPE", "Mesh type "));
  K = int(PARAM.int_value("K", "Finite element degree"));
  K2 = int(PARAM.int_value("K", "Finite element degree"));
  Kdata = int(PARAM.int_value("KDATA", "Finite element degree for data meshfem"));
  do_new = PARAM.int_value("BENCH_NEW", "bench new assembly routines");
  do_old = int(PARAM.int_value("BENCH_OLD", "bench old assembly routines"));
  do_what = int(PARAM.int_value("BENCH_WHAT", "which test do you want to run?"));
}

namespace getfem {
  template<class VECT1, class VECT2>
  void old_asm_Neumann_condition(VECT1 &B, const mesh_im &mim, const mesh_fem &mf,
				 size_type boundary, const mesh_fem &mfdata, const VECT2 &F, dim_type N)
  {
    size_type cv, nbd1, nbd2, f;
    dal::bit_vector nn = mf.convex_index(), nf;
    base_tensor t;
    pfem pf1, pf2, pf1prec = NULL, pf2prec = NULL;
    pintegration_method pim, pimprec = 0;
    bgeot::pgeometric_trans pgt, pgtprec = NULL;
    pmat_elem_type pme; pmat_elem_computation pmec = 0;

    if (&(mf.linked_mesh()) != &(mfdata.linked_mesh()))
      GMM_THROW(std::invalid_argument,
		"This assembling procedure only works on a single mesh");
  
    for (cv << nn; cv != ST_NIL; cv << nn) {
      nf = dal::bit_vector(mf.linked_mesh().region(boundary).faces_of_convex(cv));
      if (nf.card() > 0) {
	pf1 =     mf.fem_of_element(cv); nbd1 = pf1->nb_dof(cv);
	pf2 = mfdata.fem_of_element(cv); nbd2 = pf2->nb_dof(cv);
	pgt = mf.linked_mesh().trans_of_convex(cv);
	pim = mim.int_method_of_element(cv);
	if (pf1prec != pf1 || pf2prec != pf2 || pgtprec!=pgt || pimprec != pim) {
	  pme = mat_elem_product(mat_elem_base(pf1), mat_elem_base(pf2));
	  pmec = mat_elem(pme, pim, pgt);
	  pf1prec = pf1; pf2prec = pf2; pgtprec = pgt; pimprec = pim;
	}
	for (f << nf; f != ST_NIL; f << nf) {
	  pmec->gen_compute_on_face(t,mf.linked_mesh().points_of_convex(cv),f, cv);
	  base_tensor::iterator p = t.begin();
	  for (size_type i = 0; i < nbd2; i++)
	    {
	      size_type dof2 = mfdata.ind_basic_dof_of_element(cv)[i];
	      for (size_type j = 0; j < nbd1; j++, ++p)
		{
		  size_type dof1 = mf.ind_basic_dof_of_element(cv)[j];
		  for (size_type k = 0; k < N; k++) {
		    B[dof1*N + k] += F[dof2*N+k]*(*p);
		  }
		}
	    }
	  if (p != t.end()) GMM_THROW(dal::internal_error, "internal error"); 
	}
      }
    }
  }

  template<class VECT1, class VECT2>
  void old_asm_volumic_source_term(VECT1 &B, const mesh_im &mim, const mesh_fem &mf,
				   const mesh_fem &mfdata, const VECT2 &F, dim_type N)
  {
    size_type cv, nbd1, nbd2;
    dal::bit_vector nn = mf.convex_index();
    base_tensor t;
    pfem pf1, pf2, pf1prec = NULL, pf2prec = NULL;
    pintegration_method pim, pimprec = 0;
    bgeot::pgeometric_trans pgt, pgtprec = NULL;
    pmat_elem_type pme; pmat_elem_computation pmec = 0;

    if (&(mf.linked_mesh()) != &(mfdata.linked_mesh()))
      GMM_THROW(std::invalid_argument,
		"This assembling procedure only works on a single mesh");

    for (cv << nn; cv != ST_NIL; cv << nn)
      {
	pf1 =     mf.fem_of_element(cv); nbd1 = pf1->nb_dof(cv);
	pf2 = mfdata.fem_of_element(cv); nbd2 = pf2->nb_dof(cv);
	pgt = mf.linked_mesh().trans_of_convex(cv);
	pim = mim.int_method_of_element(cv);
	if (pf1prec != pf1 || pf2prec != pf2 || pgtprec != pgt || pimprec != pim)
	  {
	    pme = mat_elem_product(mat_elem_base(pf1), mat_elem_base(pf2));
	    pmec = mat_elem(pme, pim, pgt);
	    pf1prec = pf1; pf2prec = pf2; pgtprec = pgt; pimprec = pim;
	  }
	pmec->gen_compute(t, mf.linked_mesh().points_of_convex(cv), cv);
	base_tensor::iterator p = t.begin();
	for (size_type i = 0; i < nbd2; i++)
	  {
	    size_type dof2 = mfdata.ind_basic_dof_of_element(cv)[i];
	    for (size_type j = 0; j < nbd1; j++, ++p)
	      {
		size_type dof1 = mf.ind_basic_dof_of_element(cv)[j];
		for (size_type k = 0; k < N; k++) B[dof1*N + k] += F[dof2*N+k]*(*p);
	      }
	  }
	if (p != t.end()) GMM_THROW(dal::internal_error, "internal error"); 
      }
  }

  template<class MATRM, class MESH_FEM>
  void old_asm_mass_matrix_on_boundary(MATRM &M, const mesh_im &mim, const MESH_FEM &mf1,
				       const MESH_FEM &mf2, size_type boundary, dim_type N)
  {
    size_type cv, nbd1, nbd2, f;
    dal::bit_vector nn = mf1.convex_index();
    getfem::mesh_region::face_bitset nf;
    base_tensor t;
    pfem pf1, pf1prec = 0, pf2, pf2prec = 0;
    pintegration_method pim, pimprec = 0;
    bgeot::pgeometric_trans pgt, pgtprec = NULL;
    pmat_elem_type pme; pmat_elem_computation pmec = 0;
    // M(0,0) = 1.0;  ??

    if (&(mf1.linked_mesh()) != &(mf2.linked_mesh()))
      GMM_THROW(std::invalid_argument,
		"This assembling procedure only works on a single mesh");

    for (cv << nn; cv != ST_NIL; cv << nn)
      {
	nf = mf1.linked_mesh().region(boundary).faces_of_convex(cv);
	if (nf.count() > 0) {
	  pf1 = mf1.fem_of_element(cv); nbd1 = pf1->nb_dof(cv);
	  pf2 = mf2.fem_of_element(cv); nbd2 = pf2->nb_dof(cv);
	  pgt = mf1.linked_mesh().trans_of_convex(cv);
	  pim = mim.int_method_of_element(cv);
	  if (pf1prec != pf1 || pf2prec != pf2 || pgtprec != pgt 
	      || pimprec != pim) {
	    pme = mat_elem_product(mat_elem_base(pf1), mat_elem_base(pf2));
	    pmec = mat_elem(pme, pim, pgt);
	    pf1prec = pf1; pf2prec = pf2; pgtprec = pgt; pimprec = pim;
	  }

	  for (f = 0; f < MAX_FACES_PER_CV; ++f) if (nf[f]) {

	    pmec->gen_compute_on_face(t,
				      mf1.linked_mesh().points_of_convex(cv),
				      short_type(f), cv);
	    
	    base_tensor::iterator p = t.begin();
	    for (size_type i = 0; i < nbd2; i++) {
	      size_type dof2 = mf2.ind_basic_dof_of_element(cv)[i];
	      // cout << "cv = " << cv << " dof2 = " << dof2 << endl;
	      for (size_type j = 0; j < nbd1; j++, ++p) {
		size_type dof1 = mf1.ind_basic_dof_of_element(cv)[j];
		// cout << "dof1 = " << dof1 << " dof2 = " << dof2 << endl;
		for (size_type k = 0; k < N; k++)
		  M(dof1*N + k, dof2*N + k) += (*p);
	      }
	    }
	    if (p != t.end()) GMM_THROW(dal::internal_error, "internal error"); 
	  }
	}
      }
  }

  template<class MATRM, class MESH_FEM>
  void old_asm_mass_matrix(MATRM &M, const mesh_im &mim, const MESH_FEM &mf1, const MESH_FEM &mf2, dim_type N)
  {
    size_type cv, nbd1, nbd2;
    dal::bit_vector nn = mf1.convex_index();
    base_tensor t;
    pfem pf1, pf1prec = 0, pf2, pf2prec = 0;
    pintegration_method pim, pimprec = 0;
    bgeot::pgeometric_trans pgt, pgtprec = NULL;
    pmat_elem_type pme; pmat_elem_computation pmec = 0;
    // M(0,0) = 1.0;  ??

    if (&(mf1.linked_mesh()) != &(mf2.linked_mesh()))
      GMM_THROW(std::invalid_argument,
		"This assembling procedure only works on a single mesh");

    for (cv << nn; cv != ST_NIL; cv << nn)
      {
	pf1 = mf1.fem_of_element(cv); nbd1 = pf1->nb_dof(cv);
	pf2 = mf2.fem_of_element(cv); nbd2 = pf2->nb_dof(cv);
	pgt = mf1.linked_mesh().trans_of_convex(cv);
	pim = mim.int_method_of_element(cv);
	if (pf1prec != pf1 || pf2prec != pf2 || pgtprec != pgt || pimprec != pim)
	  {
	    pme = mat_elem_product(mat_elem_base(pf1), mat_elem_base(pf2));
	    pmec = mat_elem(pme, pim, pgt);
	    pf1prec = pf1; pf2prec = pf2; pgtprec = pgt; pimprec = pim;
	  }
	pmec->gen_compute(t, mf1.linked_mesh().points_of_convex(cv), cv);

	// cout << "t = " << t << endl;
      
	base_tensor::iterator p = t.begin();
	for (size_type i = 0; i < nbd2; i++)
	  {
	    size_type dof2 = mf2.ind_basic_dof_of_element(cv)[i];
	    // cout << "cv = " << cv << " dof2 = " << dof2 << endl;
	    for (size_type j = 0; j < nbd1; j++, ++p)
	      {
		size_type dof1 = mf1.ind_basic_dof_of_element(cv)[j];
		// cout << "dof1 = " << dof1 << " dof2 = " << dof2 << endl;
		for (size_type k = 0; k < N; k++)
		  M(dof1*N + k, dof2*N + k) += (*p);
	      }
	  }
	if (p != t.end()) GMM_THROW(dal::internal_error, "internal error"); 
      }
  }

  template<class MAT, class VECT>
  void old_asm_boundary_qu_term(MAT &M, 
				const mesh_im &mim, 
				const mesh_fem &mf_u, size_type boundary, 
				const mesh_fem &mf_d, const VECT &Q, dim_type N)
  {
    size_type cv;
    dal::bit_vector nn = mf_u.convex_index(), nf;
    base_tensor t;
    pfem pf_u, pf_d, pf_u_prec = NULL, pf_d_prec = NULL;
    pintegration_method pim, pimprec = 0;
    bgeot::pgeometric_trans pgt, pgtprec = NULL;
    pmat_elem_type pme; pmat_elem_computation pmec = 0;

    if (&(mf_u.linked_mesh()) != &(mf_d.linked_mesh()))
      GMM_THROW(std::invalid_argument,
		"This assembling procedure only works on a single mesh");

    for (cv << nn; cv != ST_NIL; cv << nn)
      {
	nf = dal::bit_vector(mf_u.linked_mesh().region(boundary).faces_of_convex(cv));
	if (nf.card() > 0)
	  {
	    size_type f, nbdof_u, nbdof_d;

	    pf_u = mf_u.fem_of_element(cv); nbdof_u = pf_u->nb_dof(cv);
	    pf_d = mf_d.fem_of_element(cv); nbdof_d = pf_d->nb_dof(cv);
	    pgt = mf_u.linked_mesh().trans_of_convex(cv);
	    pim = mim.int_method_of_element(cv);
	    if (pf_u_prec != pf_u || pf_d_prec != pf_d || pgtprec!=pgt 
		|| pimprec != pim)
	      {
		pme = mat_elem_product(mat_elem_base(pf_d), 
				       mat_elem_product(mat_elem_base(pf_u),
							mat_elem_base(pf_u)));
		pmec = mat_elem(pme, pim, pgt);
		pf_u_prec = pf_u; pf_d_prec = pf_d; pgtprec = pgt; pimprec = pim;
	      }
	    for (f << nf; f != ST_NIL; f << nf)
	      {
		pmec->gen_compute_on_face(t,
				       mf_u.linked_mesh().points_of_convex(cv),
					  f, cv);
		base_tensor::iterator p = t.begin();
		scalar_type vmax = gmm::vect_norminf(base_vector(t));

		for (size_type j = 0; j < nbdof_u; j++) {
		  size_type dof_j = mf_u.ind_basic_dof_of_element(cv)[j];
		  for (size_type i = 0; i < nbdof_u; i++) {
		    size_type dof_i = mf_u.ind_basic_dof_of_element(cv)[i];
		    for (size_type id = 0; id < nbdof_d; id++) {

		      size_type dof_d = mf_d.ind_basic_dof_of_element(cv)[id];

		      /* for every element of the matrix Q */
		      for (int ii=0; ii < N; ii++) {
			for (int jj=0; jj < N; jj++) {
			  /* get Q[ii][jj] for the degree of freedom 'dof_d' */
			  scalar_type data = Q[(jj*N+ii) + N*N*(dof_d)];

			  /* we filter out noise since this matrix can be used 
			     as a constraints matrix for dirichlet conditions,
			     noise may lead to 'fictive' dirichlet condition
			     (this is the case for ex. with laplace/PK(1,4)) 

			     NON NON ET NON !!
			     finaly we DON'T FILTER NOISE since it breaks 
			     the assembling of dirichlet conditions against
			     hierarchical FEMS ...
			  */
			  if (data != 0.) {// && vmax != .0 && (*p)/vmax > 1e-5) {
			    /*
			      cerr << "QU : adding " << data << "*" << (*p) << " at dof_i=" << 
			      dof_i << "*" << N << "+" << ii << ", dof_j=" << dof_i << "*" << 
			      N << "+" << ii << endl;
			    */
			    M(dof_i*N+ii, dof_j*N+jj) += data* (*p);
			  }
			}
		      }
		      p++;
		    }
		  }
		}
		if (p != t.end()) GMM_THROW(dal::internal_error, "internal error"); 
	      }
	  }
      }
  }

  template<class MAT, class VECT>
  void old_asm_stiffness_matrix_for_linear_elasticity(MAT &RM,
						      const mesh_im &mim, 
						     const mesh_fem &mf, 
						     const mesh_fem &mfdata, 
						     const VECT &LAMBDA, const VECT &MU)
  { // à verifier

    size_type cv, nbd2, N = mf.linked_mesh().dim();
    dal::bit_vector nn = mf.convex_index();
    base_tensor t;
    pfem pf1, pf2, pf1prec = NULL, pf2prec = NULL;
    pintegration_method pim, pimprec = 0;
    bgeot::pgeometric_trans pgt, pgtprec = NULL;
    pmat_elem_type pme; pmat_elem_computation pmec = 0;

    if (&(mf.linked_mesh()) != &(mfdata.linked_mesh()))
      GMM_THROW(std::invalid_argument,
		"This assembling procedure only works on a single mesh");
  
    for (cv << nn; cv != ST_NIL; cv << nn)
      {
	pf1 =     mf.fem_of_element(cv); 
	pf2 = mfdata.fem_of_element(cv); nbd2 = pf2->nb_dof(cv);
	pgt = mf.linked_mesh().trans_of_convex(cv);
	pim = mim.int_method_of_element(cv);
	if (pf1prec != pf1 || pf2prec != pf2 || pgtprec != pgt || pimprec != pim)
	  {
	    pme = mat_elem_product(mat_elem_product(mat_elem_grad(pf1),
						    mat_elem_grad(pf1)), 
				   mat_elem_base(pf2));
	    pmec = mat_elem(pme, pim, pgt);
	    pf1prec = pf1; pf2prec = pf2; pgtprec = pgt; pimprec = pim;
	  }
	pmec->gen_compute(t, mf.linked_mesh().points_of_convex(cv), cv);
	base_tensor::iterator p = t.begin();
      
	size_type nbd = mf.nb_basic_dof_of_element(cv);

	for (size_type r = 0; r < nbd2; r++)
	  {
	    size_type dof3 = mfdata.ind_basic_dof_of_element(cv)[r];
	    for (dim_type l = 0; l < N; l++)
	      for (size_type j = 0; j < nbd; j++)
		{
		  size_type dof2 = mf.ind_basic_dof_of_element(cv)[j];
	    
		  for (dim_type k = 0; k < N; k++)
		    for (size_type i = 0; i < nbd; i++, ++p)
		      {
			size_type dof1 = mf.ind_basic_dof_of_element(cv)[i];
		
			if (dof1*N + k >= dof2*N + l)
			  {
			    RM(dof1*N + k, dof2*N + l) += LAMBDA[dof3] * (*p);
			    RM(dof2*N + l, dof1*N + k) = RM(dof1*N + k, dof2*N + l);
			  }
		
			if (dof1*N + l >= dof2*N + k)
			  {
			    RM(dof1*N + l, dof2*N + k) += MU[dof3] * (*p);
			    RM(dof2*N + k, dof1*N + l) = RM(dof1*N + l, dof2*N + k);
			  }

			// cout << "matr elem : " << int(l) << " " << int(j) << " " << int(k) << " " << int(i) << " : " << *p << endl; getchar();
	      
			if (l == k && dof1 >= dof2)
			  for (size_type n = 0; n < N; ++n)
			    {
			      RM(dof1*N + n, dof2*N + n) += MU[dof3] * (*p);
			      RM(dof2*N + n, dof1*N + n) = RM(dof1*N + n, dof2*N + n);
			    }
		
		      }
		}
	  }
	if (p != t.end()) GMM_THROW(dal::internal_error, "internal error"); 
      }
  }

  template<class MAT, class VECT>
  void old_asm_mixed_pressure_term(MAT &B,
				   const mesh_im &mim, 
				   const mesh_fem &mf_u,
				   const mesh_fem &mf_p,
				   const mesh_fem &mf_d,
				   const VECT &DATA) {
    size_type cv;
    dal::bit_vector nn = mf_u.convex_index();

    base_tensor t;

    pmat_elem_computation pmec = 0;

    pfem pf_u, pf_p, pf_d;
    pfem pf_u_prec = NULL, pf_p_prec = NULL, pf_d_prec = NULL;
    pintegration_method pim, pimprec = 0;
    bgeot::pgeometric_trans pgt, pgtprec = NULL;
    size_type nbdof_u, nbdof_p, nbdof_d;
    size_type N = mf_u.linked_mesh().dim();

    if (&(mf_u.linked_mesh()) != &(mf_p.linked_mesh())
	|| &(mf_u.linked_mesh()) != &(mf_d.linked_mesh()))
      GMM_THROW(std::invalid_argument,
		"This assembling procedure only works on a single mesh");

    /* loop over all convexes */
    for (cv << nn; cv != ST_NIL; cv << nn) {

      pf_u = mf_u.fem_of_element(cv); nbdof_u = pf_u->nb_dof(cv);
      pf_p = mf_p.fem_of_element(cv); nbdof_p = pf_p->nb_dof(cv);
      pf_d = mf_d.fem_of_element(cv); nbdof_d = pf_d->nb_dof(cv);
      pgt = mf_u.linked_mesh().trans_of_convex(cv);
      pim = mim.int_method_of_element(cv);

      /* avoids recomputation of already known pmat_elem_computation */
      if (pf_u_prec != pf_u || pf_p_prec != pf_p || pf_d_prec != pf_d 
	  || pgtprec != pgt || pimprec != pim) {
	pmec = mat_elem(mat_elem_product(mat_elem_product(mat_elem_grad(pf_u),
							  mat_elem_base(pf_p)),
					 mat_elem_base(pf_d)), pim, pgt);
	pf_u_prec = pf_u;
	pf_p_prec = pf_p;
	pf_d_prec = pf_d; pgtprec = pgt; pimprec = pim;
      }
      pmec->gen_compute(t, mf_u.linked_mesh().points_of_convex(cv), cv);
      
      base_tensor::iterator p = t.begin();
      for (size_type i = 0; i < nbdof_d; i++) {
	size_type dof_d = mf_d.ind_basic_dof_of_element(cv)[i];
	for (size_type j = 0; j < nbdof_p; j++) {
	  size_type dof_p = mf_p.ind_basic_dof_of_element(cv)[j];
	  for (size_type l = 0; l < N; l++) {
	    // loop over derivation directions (d/dx, d/dy ..)
	    //	    for (size_type m = 0; m < N; m++) {
	    // loop over vector base function components (phi_x, phi_y ...)
	    for (size_type k = 0; k < nbdof_u; k++) {
	      //		if (m == l) {
	      /*
		ssert(finite(DATA[dof_d])); 
		  
		ssert(p < t.end());
		  
		ssert(finite(*p));
	      */
	      size_type dof_u = mf_u.ind_basic_dof_of_element(cv)[k];
	      B(dof_u*N+l, dof_p) += DATA[dof_d]*(*p);
	      //		}
	      p++;
	    }
	    //	    }
	  } 
	}
      }
      if (p != t.end()) GMM_THROW(dal::internal_error, "internal error"); 
    }
  }

  template<class MAT, class VECT>
  void old_asm_stiffness_matrix_for_laplacian(MAT &RM, const mesh_im &mim, const mesh_fem &mf,
					     const mesh_fem &mfdata, const VECT &A)
  { // optimisable
    size_type cv, nbd1, nbd2, N = mf.linked_mesh().dim();
    dal::bit_vector nn = mf.convex_index();
    base_tensor t;
    pfem pf1, pf2, pf1prec = 0, pf2prec = 0;
    pintegration_method pim, pimprec = 0;
    bgeot::pgeometric_trans pgt, pgtprec = 0;
    pmat_elem_computation pmec = 0;

    if (&(mf.linked_mesh()) != &(mfdata.linked_mesh()))
      GMM_THROW(std::invalid_argument,
		"This assembling procedure only works on a single mesh");

    for (cv << nn; cv != ST_NIL; cv << nn)
      {
	pf1 =     mf.fem_of_element(cv); nbd1 = pf1->nb_dof(cv);
	pf2 = mfdata.fem_of_element(cv); nbd2 = pf2->nb_dof(cv);
	pgt = mf.linked_mesh().trans_of_convex(cv);
	pim = mim.int_method_of_element(cv);
	if (pf1prec != pf1 || pf2prec != pf2 || pgtprec != pgt || pimprec != pim)
	  {
	    pmat_elem_type pme = mat_elem_product(mat_elem_product(
								   mat_elem_grad(pf1), mat_elem_grad(pf1)), mat_elem_base(pf2));
	    pmec = mat_elem(pme, pim, pgt);
	    pf1prec = pf1; pf2prec = pf2; pgtprec = pgt; pimprec = pim;
	  }
	pmec->gen_compute(t, mf.linked_mesh().points_of_convex(cv), cv);
	// cout << "elem matrix " << t << endl;
	base_tensor::iterator p = t.begin();
	for (size_type r = 0; r < nbd2; r++) {
	  size_type dof3 = mfdata.ind_basic_dof_of_element(cv)[r];
	  for (size_type l = 0; l < N; l++) {
	    for (size_type i = 0; i < nbd1; i++) {
	      size_type dof2 = mf.ind_basic_dof_of_element(cv)[i];
	      p += l * nbd1;
	      for (size_type j = 0; j < nbd1; j++, ++p) {
		size_type dof1 = mf.ind_basic_dof_of_element(cv)[j];
		if (dof1 >= dof2) { 
		  RM(dof1, dof2) += A[dof3]*(*p);
		  RM(dof2, dof1) = RM(dof1, dof2);
		}
	      }
	      p += (N-l-1) * nbd1;
	    }
	  }
	}
	if (p != t.end()) GMM_THROW(dal::internal_error, "internal error"); 
      }
  }

  template<class MESH_FEM, class VECT>
  scalar_type old_L2_norm(const mesh_im &mim, MESH_FEM &mf, const VECT &U, size_type N, const dal::bit_vector &cvlst)
  { /* optimisable */
    size_type cv;
    scalar_type no = 0.0;
    dal::bit_vector nn = cvlst;
    dal::dynamic_array<base_vector, 2> vval;
    base_tensor t;
    pfem pf1, pf1prec = NULL;
    pintegration_method pim, pimprec = 0;

    bgeot::pgeometric_trans pgt, pgtprec = NULL;
    pmat_elem_type pme; pmat_elem_computation pmec = 0;
    
    for (cv << nn; cv != ST_NIL; cv << nn)
      {
	pf1 =     mf.fem_of_element(cv);
	pgt = mf.linked_mesh().trans_of_convex(cv);
	pim = mim.int_method_of_element(cv);
	size_type nbd = mf.nb_basic_dof_of_element(cv);
	if (pf1prec != pf1 || pgtprec != pgt || pimprec != pim)
	  {
	    pme = mat_elem_product(mat_elem_base(pf1), mat_elem_base(pf1));
	    pmec = mat_elem(pme, pim, pgt);
	    pf1prec = pf1; pgtprec = pgt; pimprec = pim;
	  }
	pmec->gen_compute(t, mf.linked_mesh().points_of_convex(cv), cv);
	base_tensor::iterator p = t.begin();

	for (size_type i = 0; i < nbd; i++)
	  { 
	    size_type dof1 = mf.ind_basic_dof_of_element(cv)[i];
	    if (vval[i].size() != N) vval[i] = base_vector(N); 
	    for (size_type k = 0; k < N; k++) (vval[i])[k] = U[dof1*N+k];
	  }

	for (size_type i = 0; i < nbd; i++)
	  for (size_type j = 0; j < nbd; j++, ++p)
	    no += gmm::vect_sp(vval[i], vval[j]) * (*p);
      
      }
    return sqrt(no);
  }

  template<class MESH_FEM, class VECT>
  scalar_type old_H1_semi_norm(const mesh_im &mim, MESH_FEM &mf, const VECT &U, size_type N, const dal::bit_vector& cvlst)
  { /* optimisable */
    size_type cv, NN = mf.linked_mesh().dim();
    scalar_type no = 0.0;
    dal::bit_vector nn = cvlst;
    dal::dynamic_array<base_vector, 2> vval;
    base_tensor t;
    pfem pf1, pf1prec = NULL;
    pintegration_method pim, pimprec = 0;
    bgeot::pgeometric_trans pgt, pgtprec = NULL;
    pmat_elem_type pme; pmat_elem_computation pmec = 0;

    for (cv << nn; cv != ST_NIL; cv << nn)
      {
	pf1 =     mf.fem_of_element(cv);
	pgt = mf.linked_mesh().trans_of_convex(cv);
	pim = mim.int_method_of_element(cv);
	size_type nbd = mf.nb_basic_dof_of_element(cv);
	if (pf1prec != pf1 || pgtprec != pgt || pimprec != pim)
	  {
	    pme = mat_elem_product(mat_elem_grad(pf1), mat_elem_grad(pf1));
	    pmec = mat_elem(pme, pim, pgt);
	    pf1prec = pf1; pgtprec = pgt; pimprec = pim;
	  }
	pmec->gen_compute(t, mf.linked_mesh().points_of_convex(cv), cv);
	base_tensor::iterator p = t.begin();
	for (size_type i = 0; i < nbd; i++)
	  { 
	    size_type dof1 = mf.ind_basic_dof_of_element(cv)[i];
	    if (vval[i].size() != N) vval[i] = base_vector(N); 
	    for (size_type k = 0; k < N; k++) (vval[i])[k] = U[dof1*N+k];
	  }
	for (size_type l = 0; l < NN; l++)
	  for (size_type i = 0; i < nbd; i++)
	    for (size_type k = 0; k < NN; k++)
	      for (size_type j = 0; j < nbd; j++, ++p)
		if (k == l)
		  no += (*p) * gmm::vect_sp(vval[i], vval[j]);
      }
    return sqrt(no);
  }

  template<class MESH_FEM, class VECT>
  scalar_type old_H1_norm(const mesh_im &mim, MESH_FEM &mf, const VECT &U, size_type N, const dal::bit_vector& cvlst) {
    return sqrt( gmm::sqr(old_L2_norm(mim, mf, U, N, cvlst)) 
		 + gmm::sqr(old_H1_semi_norm(mim, mf, U, N, cvlst)));
  }


  /* old2 *******************************************************************
     inline reduction tests */

  template<class MAT, class VECT>
    void old2_asm_stiffness_matrix_for_linear_elasticity(const MAT &RM_,
							 const mesh_im &mim, 
                                                         const mesh_fem &mf,
                                                         const mesh_fem &mfdata,
                                                         const VECT &LAMBDA,const VECT &MU) {
    MAT &RM = const_cast<MAT &>(RM_);
    if (mfdata.get_qdim() != 1)
      GMM_THROW(invalid_argument, "invalid data mesh fem (Qdim=1 required)");
    
    if (mf.get_qdim() != mf.linked_mesh().dim())
      GMM_THROW(std::logic_error, "wrong qdim for the mesh_fem");
    generic_assembly assem("lambda=data$1(#2); mu=data$2(#2);"
			   "M(#1,#1)+= sym(comp(vGrad(#1)(:,i,j).vGrad(#1)(:,i,j).Base(#2)(k).mu(k)) +"
			   "               comp(vGrad(#1)(:,j,i).vGrad(#1)(:,i,j).Base(#2)(k).mu(k)) +"
			   "               comp(vGrad(#1)(:,i,i).vGrad(#1)(:,j,j).Base(#2)(k).lambda(k)));");
    assem.push_mi(mim);
    assem.push_mf(mf);
    assem.push_mf(mfdata);
    assem.push_data(LAMBDA);
    assem.push_data(MU);
    assem.push_mat(RM);
    assem.assembly();
  }

  template<typename VEC>
  scalar_type old2_asm_L2_norm(const mesh_im &mim, const mesh_fem &mf, const VEC &U) {
    generic_assembly assem;    
    if (mf.get_qdim() == 1)
      assem.set("u=data(#1); v=u; V()+=comp(Base(#1)(i).Base(#1)(j).u(i).v(j))");
    else
      assem.set("u=data(#1); v=u;"
		"V()+=comp(vBase(#1)(i,k).vBase(#1)(j,k).u(i).v(j))");
    assem.push_mi(mim);
    assem.push_mf(mf);
    assem.push_data(U);
    base_vector v(1);
    assem.push_vec(v);
    assem.assembly();
    return sqrt(v[0]);
  }

  template<typename VEC>
  scalar_type old2_asm_H1_norm(const mesh_im &mim, const mesh_fem &mf, const VEC &U) {
    generic_assembly assem;    
    if (mf.get_qdim() == 1)
      assem.set("u=data(#1); V()+=comp(Grad(#1)(i,d).Grad(#1)(j,d).u(i).u(j))");
    else
      assem.set("u=data(#1);"
		"V()+=comp(vGrad(#1)(i,k,d).vGrad(#1)(j,k,d).u(i).u(j))");
    assem.push_mi(mim);
    assem.push_mf(mf);
    assem.push_data(U);
    base_vector v(1);
    assem.push_vec(v);
    assem.assembly();
    return sqrt(v[0] + gmm::sqr(old2_asm_L2_norm(mim,mf,U)));
  }

} /* namespace getfem */


void gen_mesh(getfem::mesh& mesh) {
  cout << "Mesh generation, N=" << param.NX << " Ndim=" << param.Ndim << endl;
  base_node org(param.Ndim); gmm::clear(org);
  std::vector<base_small_vector> vtab(param.Ndim);
  std::vector<size_type> ref(param.Ndim); std::fill(ref.begin(), ref.end(), param.NX);
  for (size_type i = 0; i < param.Ndim; i++) { 
    vtab[i] = base_small_vector(param.Ndim); gmm::clear(vtab[i]);
    (vtab[i])[i] = 1. / scalar_type(param.NX);
  }
  switch (param.mesh_type) {
  case 0: getfem::parallelepiped_regular_simplex_mesh(mesh, dim_type(param.Ndim), org,
						      vtab.begin(), ref.begin()); 
    cerr << mesh.convex_index().card() << " " << param.Ndim << "D simplexes generated\n";
    break;
  case 1 : getfem::parallelepiped_regular_mesh
      (mesh, dim_type(param.Ndim), org, vtab.begin(), ref.begin()); 
    cerr << mesh.convex_index().card() << " " << param.Ndim << "D parallelepipeds generated\n";
    break;
  case 2 : getfem::parallelepiped_regular_prism_mesh
      (mesh, dim_type(param.Ndim), org, vtab.begin(), ref.begin()); 
    cerr << mesh.convex_index().card() << " " << param.Ndim << "D prisms generated\n";
    break;
  default : GMM_THROW(dal::internal_error, "Unknown type of mesh");
  }

  assert(param.NX>2);
  /* un ptit trou dans la liste des convexes ne fait pas de mal */
  mesh.sup_convex(param.NX/2);
  mesh.sup_convex(param.NX/2 + 1);
  mesh.optimize_structure();

  /* bouge un peu les noeuds */
  /*  for (size_type i=0; i < mesh.points().size(); ++i) {
    for (size_type j=0; j < param.Ndim; ++j) {
      float d = ((rand() % 100)-50)/(500.*param.NX);
      mesh.points()[i][j] += d;
    }
    }*/
  for (unsigned cv=0; cv < std::min(mesh.convex_index().card(),
			   param.NX*param.Ndim*param.Ndim*10); cv += 2) {
    mesh.region(1).add(cv, (cv/4) % (param.Ndim > 1 ? 3 : 2)); 
  }
  mesh.region(1).add(0,0);
}

void init_mesh_fem(getfem::mesh_fem &mf, bool datamf) {
  if (datamf)
    mf.set_classical_finite_element(dim_type(param.Kdata));
  else {
    dal::bit_vector cvlst = mf.linked_mesh().convex_index();
    for (dal::bv_visitor cv(cvlst); !cv.finished(); ++cv) {
      bgeot::pgeometric_trans pgt = mf.linked_mesh().trans_of_convex(cv);
      if ((cv+1) % 100) {
	mf.set_finite_element(cv, getfem::classical_fem(pgt,short_type(param.K)));
      } else {
	mf.set_finite_element(cv, getfem::classical_fem(pgt,short_type(param.K2)));
      }
    }
  }
}

void init_mesh_im(getfem::mesh_im &mim, bool use_exact_im=true) {
  size_type cv;
  dal::bit_vector cvlst = mim.linked_mesh().convex_index();
  for (cv << cvlst; cv != size_type(-1); cv << cvlst) {      
    bgeot::pgeometric_trans pgt = mim.linked_mesh().trans_of_convex(cv);
    if ((cv+1) % 100) {
      mim.set_integration_method(cv, 
				 (use_exact_im && (rand() % 10)==0) ? getfem::classical_exact_im(pgt) : 
				 getfem::classical_approx_im(pgt,dim_type(param.K*3)));
    } else {
      mim.set_integration_method(cv, 
				 (use_exact_im && (rand() % 10)==0)  ? getfem::classical_exact_im(pgt) : 
				 getfem::classical_approx_im(pgt,dim_type(param.K2*3)));
    }
  }
}

void comp_mat(const sparse_matrix_type& M1, const sparse_matrix_type& M2)
{
  scalar_type d = 0;
  scalar_type mx = 1e-200; /* avoid triggering an FPE for bound assembly when there is no boundary */
  sparse_vector_type r(gmm::mat_ncols(M1));
  for (size_type i = 0; i < gmm::mat_nrows(M1); ++i) {
    mx = std::max(mx,gmm::vect_norminf(gmm::mat_const_row(M1,i)));
    mx = std::max(mx,gmm::vect_norminf(gmm::mat_const_row(M2,i)));
    /*    int r = gmm::add(gmm::scaled(gmm::mat_const_row(M1,i), -1.0),
	  gmm::mat_row(M2,i));*/
    gmm::copy(gmm::mat_const_row(M2,i),r);
    gmm::add(gmm::scaled(gmm::mat_const_row(M1,i), -1.0),r);
    scalar_type d2 = gmm::vect_norminf(r);
    d = std::max(d,d2);
    if (mx > 1e-10 && d/mx > 1e-6) {
      sparse_vector_type r1(gmm::mat_ncols(M1));
      sparse_vector_type r2(gmm::mat_ncols(M2));
      gmm::copy(gmm::mat_const_row(M1,i),r1);
      gmm::copy(gmm::mat_const_row(M2,i),r2);    
      cout << "\nrow(" << i+1 << "),\nM1=" << r1 << "\nM2=" << r2 << endl;
      fail_cnt++;
      cout << " FAILED !";
      break;
    }
  }
  assert(mx!=0.);
  cout << " ---> difference between assemblies: " << d / mx << "\n\n";
}

void comp_vec(const base_vector& V1, const base_vector& V2)
{
  scalar_type mx = std::max(gmm::vect_norminf(V1),gmm::vect_norminf(V2));
  base_vector dv = V2;
  gmm::add(gmm::scaled(V1, -1.0),dv);
  scalar_type d = gmm::vect_norminf(dv);
  if (mx != 0. && d/mx > 1e-6) {
    fail_cnt++;
    cout << " FAILED !";
  }
  assert(mx!=0.);
  cout << " ---> difference between assemblies: " << d / mx << "\n\n";
}

void comp_scal(scalar_type a, scalar_type b) {
  scalar_type d = gmm::abs(a-b)/std::max(gmm::abs(a),gmm::abs(b));
  if (d > 1e-10) {
    fail_cnt++;
    cout << " FAILED !";
  }
  cout << " ---> difference between assemblies: " << d << "\n\n";
}

#endif /* ASSEMBLY_CHECK */

base_node mknode(double a,double b,double c) {
  base_node n(3); n[0]=a; n[1]=b; n[2]=c; return n;
}
base_node mknode(double a,double b) {
  base_node n(2); n[0]=a; n[1]=b; return n;
}

void tensor_shape_check() {
  bgeot::tensor_ranges r1(5); r1[0] = 2; r1[1]=1; r1[2]=2; r1[3]=3; r1[4]=2;
  bgeot::tensor_ranges r2(4); r2[0] = 2; r2[1]=2; r2[2]=3; r2[3]=2;
  
  bgeot::tensor_shape m1(r1),m2(r2);

    cerr << "m1=\n" << m1 << endl;

  cerr << "m2=\n" << m2 << endl;

  cerr << "slice_shape(m1, 1, 0)=" << m1.slice_shape(bgeot::tensor_mask::Slice(1, 0)) << endl;
    

  bgeot::tensor_shape m3(m1.slice_shape(bgeot::tensor_mask::Slice(1, 0)));

  m3.remove_mask(1);m3.shift_dim_num_ge(1,-1);
  m3.set_ndim_noclean(4);m3.update_idx2mask();
  cerr << "m3=slice(m1)=\n" << m3 << endl;

  bgeot::tensor_shape m4(m2.diag_shape(bgeot::tensor_mask::Diagonal(0,1)));
  cerr << "m4=diag(m2)=\n" << m4 << endl;

  bgeot::tensor_shape m5(m4.diag_shape(bgeot::tensor_mask::Diagonal(1,3)));
  cerr << "m5=diag(m4)=\n" << m5 << endl;

  assert(m5.card()==6);

  bgeot::tensor_shape m6(m3); 
  m6.merge(m5, true);
  cerr << "m6=m5.and.m3=\n" << m6 << endl;
  assert(m6.card()==6);


  bgeot::tensor_shape m7(m3); 
  m7.merge(m5, false);
  //cerr << "m7=m5.or.m3=\n" << m7 << endl;
  assert(m7.card() == 24);
}

void tensor_ref_check() {
  scalar_type s1_[] = {1.0,2.0,3.0, 4.,5.,6., 7.,8.,9., 10.,11.,12.,13.,14.,15.,16.};
  scalar_type *s1 = s1_;
  bgeot::tensor_ranges r1(3); r1[0]=3; r1[1]=2; r1[2]=2;
  bgeot::tensor_ref tr1(r1,&s1);
  cerr << "tr1=" << tr1 << endl;
  
  bgeot::tensor_ref tr2(tr1, bgeot::tensor_mask::Slice(0,1));
  cerr << "tr2=tr1(1,:,:)=" << tr2 << endl;

  bgeot::tensor_ref tr20(tr1, bgeot::tensor_mask::Slice(1,1));
  cerr << "tr20=tr1(:,1,:)=" << tr20 << endl;

  bgeot::tensor_ref tr21(tr1, bgeot::tensor_mask::Slice(2,1));
  cerr << "tr21=tr1(:,:,1)=" << tr21 << endl;

  bgeot::tensor_ref tr22(tr21, bgeot::tensor_mask::Slice(1,1));
  cerr << "tr22=tr1(:,1,1)=" << tr22 << endl;

  bgeot::tensor_ref tr3(tr2, bgeot::tensor_mask::Diagonal(0,1));
  cerr << "tr3=tr2(i,i)=[2 0;0 11]=" << tr3 << endl;

  bgeot::tensor_ranges r2(4); r2[0] = 2; r2[1]=2; r2[2]=2; r2[3]=2;
  bgeot::tensor_ref tr4(r2, &s1);
  cerr << "tr4=" << tr4 << endl;

  bgeot::tensor_ref tr5_(bgeot::tensor_ref(tr4, bgeot::tensor_mask::Diagonal(2,3)));
  
  bgeot::tensor_ref tr5(bgeot::tensor_ref(tr5_, bgeot::tensor_mask::Diagonal(0,1)));

  cerr << "@@@@@@@@@@@@@-------------------------------------------\n" 
       << "tr5=tr4(i,i,j,j)=" << tr5 << endl;
  
  cerr << "-------------------------------------------reduction en cours...\n"; 
  bgeot::tensor_reduction red; red.insert(tr5, " i i");
  red.prepare(NULL); 
  red.do_reduction();
 bgeot::tensor_ref tr6; red.result(tr6);
  cerr << "@@@@@@@@@@@@@@@@@-------------------------------------------\n"; 
  cerr << "tr6=sum(i,tr5(:,i,:,i))=[1 0; 0 16]=" << tr6 << endl;
  assert(tr6.base()[0]==1 && 
	 tr6.base()[1]==0 && 
	 tr6.base()[2]==0 && 
	 tr6.base()[3]==16);
  cerr << "-------------------------------------------reduction 2 en cours...\n" ;
  red.clear();
  red.insert(tr5, "  kl");
  red.prepare(NULL); 
  red.do_reduction();
  red.result(tr6);
  cerr << "@@@@@@@@@@@@@@@@@-------------------------------------------\n"; 
  cerr << "sum(i,tr5(:,:,i,j))=[14 0; 0 20]=" << tr6 << endl;
  assert(tr6.base()[0]==14 && 
	 tr6.base()[1]==0 && 
	 tr6.base()[2]==0 && 
	 tr6.base()[3]==20);
  

  red.clear();
  red.insert(tr3, "ij");
  red.insert(tr5, "ijkl");

  red.prepare(NULL); 
  red.do_reduction();
  bgeot::tensor_ref tr7; red.result(tr7);
  cerr << "@@@@@@@@@@@@@@@@@-------------------------------------------\n"; 
  cerr << "tr7=sum(tr3(i,j)*tr5(i,j,l,k))=" << tr7 << endl;
  assert(tr7.base()[0] == 248.);
  

  red.clear();
  red.insert(tr4, "ijij");
  red.prepare(NULL); 
  red.do_reduction();
  bgeot::tensor_ref tr8; red.result(tr8);
  cerr << "@@@@@@@@@@@@@@@@@-------------------------------------------\n"; 
  cerr << "tr8=sum(i,j,tr4(i,j,i,j))=" << tr8 << endl;
  assert(tr8.base()[0] == 34.);
  
}

void tensor_ref_check2() {
  cout << "more checks with strange strides..\n";
  /* NOTE : ALTHOUGH THIS TEST PASSES, THERE IS SOMETHING BROKEN WHEN
     STRIDES.SIZE() != CARD() .. do not use that for emulation symmetricy
  */
  scalar_type s1_[] = {1.0,2.0,3.0,4.,5.,6., 7.,8.,9., 10.,11.,12.,13.,14.,15.,16.,17.,18.};
  std::vector<scalar_type> s1(s1_,  s1_+ sizeof s1_/sizeof(scalar_type));

  bgeot::tensor_ref tr1;
  tr1.set_ndim_noclean(3);
  bgeot::tensor_mask m0; m0.set_full(0,4);
  bgeot::tensor_strides strd0(4); std::fill(strd0.begin(),strd0.end(),0); strd0[1] = 1;
  tr1.push_mask(m0); tr1.strides().push_back(strd0);
  bgeot::tensor_mask m1; m1.set_full(1,3);
  bgeot::tensor_strides strd1(3); strd1[0] = 0; strd1[1] = 2; strd1[2] = 4;
  tr1.push_mask(m1); tr1.strides().push_back(strd1);
  bgeot::tensor_mask m2; m2.set_full(2,3);
  bgeot::tensor_strides strd2(3); strd2[0] = 6; strd2[1] = 0; strd2[2] = 6;
  tr1.push_mask(m2); tr1.strides().push_back(strd2);
  
  scalar_type *pbase = &s1[0];
  tr1.set_base(pbase);
  
  cerr << "tr1=" << tr1 << endl;

  scalar_type s2_[] = {1.0,2.0,3.0, 4.,5.,6., 7.,8.,9., 10.,11.,12.,13.,14.,15.,16.};
  scalar_type *s2 = s2_;
  bgeot::tensor_ranges r2(3); r2[0]=3; r2[1]=2; r2[2]=2;
  bgeot::tensor_ref tr2(r2,&s2);

  bgeot::tensor_reduction red; 
  red.insert(tr1, " ii");
  //red.insert(tr2, "i  ");
  red.prepare(NULL); 
  red.do_reduction();
  bgeot::tensor_ref tr9; red.result(tr9);
  
  cerr << "tr9 = " << tr9 << endl;
}  

bgeot::tensor_ref tr_from_matrix(const base_matrix &A, scalar_type *&p) {
  bgeot::tensor_ranges r(2); r[0] = unsigned(A.nrows()); r[1] = unsigned(A.ncols());
  bgeot::tensor_ref tr(r); tr.set_base(p);
  return tr;
}

void tensor_ref_check3(unsigned n1, unsigned n2, unsigned n3, unsigned n4, unsigned n5) {
  base_matrix A(n1,n2); base_matrix B(n2,n3); base_matrix C(n3,n4); base_matrix D(n4,n5);
  gmm::fill_random(A); gmm::fill_random(B); gmm::fill_random(C); gmm::fill_random(D);
  base_matrix AB(n1,n3); gmm::mult(A,B,AB);
  base_matrix ABC(n1,n4); gmm::mult(AB,C,ABC);
  base_matrix BC(n2,n4); gmm::mult(B,C,BC);
  base_matrix ABCD(n1,n5); gmm::mult(ABC,D,ABCD);
  scalar_type *pA = &A[0], *pB = &B[0], *pC = &C[0], *pD = &D[0];
  bgeot::tensor_ref trA = tr_from_matrix(A,pA);
  bgeot::tensor_ref trB = tr_from_matrix(B,pB);
  bgeot::tensor_ref trC = tr_from_matrix(C,pC);
  bgeot::tensor_ref trD = tr_from_matrix(D,pD);
  bgeot::tensor_reduction red;
  red.insert(trC, "jk");
  red.insert(trB, "ij");
  red.insert(trA, " i");
  red.insert(trD, "k ");
  cout << "A=" << A << "\nBC = " << BC << "\n";
  red.prepare(NULL); red.do_reduction();
  bgeot::tensor_ref trABCD; red.result(trABCD);
  cout << "Final: " << trABCD << "\n";
  cout << "ABCD = " << ABCD << "\n =?= " << "\n";
  for (unsigned j=0; j < n5; ++j)
    for (unsigned i=0; i < n1; ++i) {
      if (gmm::abs(trABCD.base()[i+j*n1] - ABCD(i,j)) > 1e-10) {
	cerr << "FAILED : " << i << ", " << j << ", " << trABCD.base()[i+j*n1] << "!=" << ABCD(i,j) << "\n";
	GMM_ASSERT1(false, "");
      }
    }
}

void
do_general_check() {
  tensor_shape_check();
  tensor_ref_check();  
  cerr << "Basic check OK..\n";
  tensor_ref_check3(4,2,3,2,5);
  cerr << "Advanced tensor check OK..\n";
}


double nrand() { return (::rand() % 10000) / 10000. + 0.01; }

#ifdef ASSEMBLY_CHECK

void
run_tests(getfem::mesh_im &mim, 
	  getfem::mesh_fem& mf, getfem::mesh_fem& mfq,
	  getfem::mesh_fem& mfd, getfem::mesh_fem& mfdq,
	  bool do_new, bool do_old, const std::vector<bool>& do_what, unsigned nloop, unsigned nloop_bound) {
  size_type Ndim = mf.linked_mesh().dim();
  bool do_new2 = do_new;
  base_vector V1q(Ndim*mf.nb_dof()), V2q(mfq.nb_dof());
  base_vector V1(mf.nb_dof()), V2(mf.nb_dof());
  sparse_matrix_type M1(mfq.nb_dof(),mfq.nb_dof()), M2(mfq.nb_dof(),mfq.nb_dof());

  chrono c;
    

  cout << "mf.nb_dof=" << mf.nb_dof() << " mfq=" << mfq.nb_dof() << endl;
  cout << "mfd.nb_dof=" << mfd.nb_dof() << " mfdq=" << mfdq.nb_dof() << endl;

  base_vector A(mfd.nb_dof()); std::generate(A.begin(), A.end(), nrand);
  base_vector A2(mfd.nb_dof()); std::generate(A2.begin(), A2.end(), nrand);
  base_vector Aq(mfdq.nb_dof()); std::generate(Aq.begin(), Aq.end(), nrand);
  scalar_type s1=0,s2=0;

  /* --- BOUNDARY MASS MATRIX --- */
  if (do_what[DO_BOUNDARY_MASS]) {
    if (do_old) {
      cout << "boundary mass matrix, old way [" << nloop_bound << " times] .." << flushy;
      c.init();
      for (size_type cnt = 0; cnt < nloop_bound; ++cnt) {
	gmm::clear(M1); c.tic();
	getfem::old_asm_mass_matrix_on_boundary(M1, mim, mf, mfd, 1, dim_type(Ndim));
	c.toc(); cout << "#" << flushy; 
      }
      cout << "done " << c << endl;
    }
    if (do_new) {
      cout << "boundary mass matrix, new way [" << nloop_bound << " times] .." << flushy;
      c.init();
      for (size_type cnt = 0; cnt < nloop_bound; ++cnt) {
	gmm::clear(M2); c.tic();
	getfem::asm_mass_matrix(M2, mim, mfq, mfdq, size_type(1));
	c.toc(); cout << "#" << flushy;
      }
      cout << "done " << c << endl;    
    }
    if (do_old && do_new) comp_mat(M1,M2);
  }


  /* --- SCALAR VOLUMIC SOURCE --- */
  if (do_what[DO_SCAL_VOLUMIC_SOURCE]) {
    if (do_old) {
      cout << "volumic source, Q=" << 1 << ", old way [" << nloop_bound << " times] .." << flushy;
      c.init();
      for (size_type cnt = 0; cnt < nloop_bound; ++cnt) {
	gmm::clear(V1); c.tic(); //gmm::resize(M1, mfq.nb_dof(),mfq.nb_dof());
	getfem::old_asm_volumic_source_term(V1, mim, mf, mfd, A, 1u);
	c.toc(); cout << "#" << flushy;
      }
      cout << "done " << c << endl;
    }
    if (do_new) {
      cout << "volumic source, Q=" << 1 << ", new way [" << nloop_bound << " times] .." << flushy;
      c.init();
      for (size_type cnt = 0; cnt < nloop_bound; ++cnt) {
	gmm::clear(V2); c.tic();
	getfem::asm_source_term(V2, mim, mf, mfd, A);
	c.toc(); cout << "#" << flushy;
      }
      cout << "done " << c << endl;
    }
    if (do_old && do_new) comp_vec(V1,V2);
  }
  //  cerr << "V1(old)=" << V1 << endl;
  //cerr << "V2(new)=" << V2 << endl;

  /* --- VECTOR VOLUMIC SOURCE --- */
  if (do_what[DO_VEC_VOLUMIC_SOURCE]) {
    if (do_old) {
      cout << "volumic source, Q=" << Ndim << ", old way [" << nloop_bound << " times] .." << flushy;
      c.init();
      for (size_type cnt = 0; cnt < nloop_bound; ++cnt) {
	gmm::clear(V1q); c.tic(); //gmm::resize(M1, mfq.nb_dof(),mfq.nb_dof());
	getfem::old_asm_volumic_source_term(V1q, mim, mf, mfd, Aq, dim_type(Ndim));
	c.toc(); cout << "#" << flushy;
      }
      cout << "done " << c << endl;
    }
    if (do_new) {
      cout << "volumic source, Q=" << Ndim << ", new way [" << nloop_bound << " times] .." << flushy;
      c.init();
      for (size_type cnt = 0; cnt < nloop_bound; ++cnt) {
	gmm::clear(V2q); c.tic();
	getfem::asm_source_term(V2q, mim, mfq, mfd, Aq);
	c.toc(); cout << "#" << flushy;
      }
      cout << "done " << c << endl;
    }  
    if (do_old && do_new) comp_vec(V1q,V2q);
  }

  /* --- SCALAR MASS MATRIX --- */
  if (do_what[DO_SCAL_MASS_MATRIX]) {
    if (do_old) {
      cout << "mass matrix, Q=" << 1 << ", old way [" << nloop << " times] .." << flushy;
      c.init();
      for (size_type cnt = 0; cnt < nloop; ++cnt) {
	gmm::clear(M1); c.tic(); //gmm::resize(M1, mfq.nb_dof(),mfq.nb_dof());
	getfem::old_asm_mass_matrix(M1, mim, mf, mfd, 1);
      c.toc(); cout << "#" << flushy;
    }
    cout << "done " << c << endl;
  }
  if (do_new) {
    cout << "mass matrix, Q=" << 1 << ", new way [" << nloop << " times] .." << flushy;
    c.init();
    for (size_type cnt = 0; cnt < nloop; ++cnt) {
      gmm::clear(M2); c.tic(); 
      getfem::asm_mass_matrix(M2, mim, mf, mfd);
      c.toc(); cout << "#" << flushy;
    }
    cout << "done " << c << endl;
  }
  if (do_old && do_new) comp_mat(M1,M2);
  }

  /* --- VECTOR MASS MATRIX --- */
  if (do_what[DO_VEC_MASS_MATRIX]) {
  if (do_old) {
    cout << "mass matrix, Q=" << Ndim << ", old way [" << nloop << " times] .." << flushy;
    c.init();
    for (size_type cnt = 0; cnt < nloop; ++cnt) {
      gmm::clear(M1); c.tic(); //gmm::resize(M1, mfq.nb_dof(),mfq.nb_dof());
      getfem::old_asm_mass_matrix(M1, mim, mf, mfd, dim_type(Ndim));
      c.toc(); cout << "#" << flushy;
    }
    cout << "done " << c << endl;
  }
  if (do_new) {
    cout << "mass matrix, Q=" << Ndim << ", new way [" << nloop << " times] .." << flushy;
    c.init();
    for (size_type cnt = 0; cnt < nloop; ++cnt) {
      gmm::clear(M2); c.tic();
      getfem::asm_mass_matrix(M2, mim, mfq, mfdq);
      c.toc(); cout << "#" << flushy;
    }
    cout << "done " << c << endl;
  }
  if (do_old && do_new) comp_mat(M1,M2);
  }



  /* ---- SCALAR LAPLACIAN ---- */
  if (do_what[DO_SCAL_LAPLACIAN]) {
  if (do_old) {
    cout << "laplacian, Q=1, old way [" << nloop << " times] .." << flushy;
    c.init();
    for (size_type cnt = 0; cnt < nloop; ++cnt) {
      gmm::clear(M1); c.tic();
      getfem::old_asm_stiffness_matrix_for_laplacian(M1, mim, mf, mfd, A);
      c.toc(); cout << "#" << flushy;
    }
    cout << "done " << c << endl;
  }
  if (do_new) {
    cout << "laplacian, Q=1, new way [" << nloop << " times] .." << flushy;
    c.init();
    for (size_type cnt = 0; cnt < nloop; ++cnt) {
      gmm::clear(M2); c.tic();
      getfem::asm_stiffness_matrix_for_laplacian(M2, mim, mf, mfd, A); 
      c.toc(); cout << "#" << flushy;
    }
    cout << "done " << c << endl;
  }
  if (do_old && do_new) comp_mat(M1,M2);
  }

  /* ---- L2 NORM, Q=1 ---- */
  if (do_what[DO_SCAL_L2_NORM]) {
    for (size_type i=0; i < mf.nb_dof(); ++i)
      { V1[i] = V2[i] = float(rand())/float(RAND_MAX); }
    if (do_old) {
      cout << "L2 norm, Q=" << 1 << ", old way [" << nloop << " times] .." << flushy;
      c.init();
      for (size_type cnt = 0; cnt < nloop; ++cnt) {
	c.tic();
	s1 = getfem::old_L2_norm(mim, mf, V1, 1, mf.convex_index());
	c.toc(); cout << "#" << flushy;
      }
      cout << "done " << c << endl;
    }
    if (do_new) {
      cout << "L2 norm, Q=" << 1 << ", new way [" << nloop << " times] .." << flushy;
      c.init();
      for (size_type cnt = 0; cnt < nloop; ++cnt) {
	c.tic();
	s2 = getfem::asm_L2_norm(mim, mf, V2);
	c.toc(); cout << "#" << flushy;
      }
      cout << "done " << c << endl;
    }
    if (do_old && do_new) comp_scal(s1,s2);
    if (do_new2) {
      cout << "L2 norm, Q=" << 1 << ", new way2 [" << nloop << " times] .." << flushy;
      c.init();
      for (size_type cnt = 0; cnt < nloop; ++cnt) {
	c.tic();
	s2 = getfem::old2_asm_L2_norm(mim, mf, V2);
	c.toc(); cout << "#" << flushy;
      }
      cout << "done " << c << endl;
    }
    if (do_old && do_new2) comp_scal(s1,s2);
  }

  /* ---- VECT H1 NORM ---- */
  if (do_what[DO_VECT_H1_NORM]) {
    for (size_type i=0; i < mfq.nb_dof(); ++i)
      { V1q[i] = V2q[i] = float(rand())/float(RAND_MAX); }
    if (do_old) {
      cout << "H1 norm, Q=" << Ndim << ", old way [" << nloop << " times] .." << flushy;
      c.init();
      for (size_type cnt = 0; cnt < nloop; ++cnt) {
	c.tic();
	s1 = getfem::old_H1_norm(mim, mf, V1q, Ndim, mf.convex_index());
	c.toc(); cout << "#" << flushy;
      }
      cout << "done " << c << endl;
    }
    if (do_new) {
      cout << "H1 norm, Q=" << Ndim << ", new way [" << nloop << " times] .." << flushy;
      c.init();
      for (size_type cnt = 0; cnt < nloop; ++cnt) {
	c.tic();
	s2 = getfem::asm_H1_norm(mim, mfq, V2q);
	c.toc(); cout << "#" << flushy;
      }
      cout << "done " << c << endl;
    }
    if (do_old && do_new) comp_vec(V1q,V2q);

    if (do_new2) {
      cout << "H1 norm, Q=" << Ndim << ", new way2 [" << nloop << " times] .." << flushy;
      c.init();
      for (size_type cnt = 0; cnt < nloop; ++cnt) {
	c.tic();
	s2 = getfem::old2_asm_H1_norm(mim, mfq, V2q);
	c.toc(); cout << "#" << flushy;
      }
      cout << "done " << c << endl;
    }
    if (do_old && do_new2) comp_vec(V1q,V2q);
  }


  /* ---- LINEAR ELASTICITY ---- */
  if (do_what[DO_LIN_ELAST]) {
  if (do_old) {
    cout << "linear elasticity, Q=" << Ndim<<", old way [" << nloop << " times] .." << flushy;
    c.init();
    for (size_type cnt = 0; cnt < nloop; ++cnt) {
      gmm::clear(M1); c.tic();
      getfem::old_asm_stiffness_matrix_for_linear_elasticity(M1, mim, mf, mfd, A, A2);
      c.toc(); cout << "#" << flushy;
    }
    cout << "done " << c << endl;
  }
  if (do_new) {
    cout << "linear elasticity, Q=" << Ndim<<", new way [" << nloop << " times] .." << flushy;
    c.init();
    for (size_type cnt = 0; cnt < nloop; ++cnt) {
      gmm::clear(M2); c.tic();
      getfem::asm_stiffness_matrix_for_linear_elasticity(M2, mim, mfq, mfd, A, A2);
      c.toc(); cout << "#" << flushy;
    }
    cout << "done " << c << endl;

    cout << "linear elasticity, Q=" << Ndim<<", new way2 [" << nloop << " times] .." << flushy;
    c.init();
    for (size_type cnt = 0; cnt < nloop; ++cnt) {
      gmm::clear(M2); c.tic();
      getfem::old2_asm_stiffness_matrix_for_linear_elasticity(M2, mim, mfq, mfd, A, A2);
      c.toc(); cout << "#" << flushy;
    }
    cout << "done " << c << endl;
  }
  if (do_old && do_new) comp_mat(M1,M2);
  }
}


struct dummy_nonlin : public getfem::nonlinear_elem_term {
  unsigned i,j;
  bgeot::multi_index sizes_;
  dummy_nonlin(size_type N) : sizes_(2)
  { sizes_[0] = sizes_[1] = short_type(N); }
  const bgeot::multi_index &sizes() const { return sizes_; }
  virtual void compute(getfem::fem_interpolation_context& /*ctx*/,
		       bgeot::base_tensor &t) {
    t.adjust_sizes(sizes_); std::fill(t.begin(), t.end(), 0.);
    t[j*sizes_[0]+i] = 1.0;
  }
};

void test_nonlin(const getfem::mesh_im &mim, const getfem::mesh_fem &mf)
{
  size_type N = mf.linked_mesh().dim();
  dummy_nonlin bidon(N);
  cerr << "testing assembly of nonlinear terms\n";
  for (bidon.i=0; bidon.i < N; ++bidon.i) {
    for (bidon.j=0; bidon.j < N; ++bidon.j) {
      std::vector<scalar_type> V1(mf.nb_dof()), V2(mf.nb_dof());
      char s[512]; sprintf(s,"t=comp(NonLin(#1).vGrad(#1));"
			   "V$1(#1) += t(i,j,:,i,j); "
			   "V$2(#1) += comp(vGrad(#1))(:,%d,%d)", bidon.i+1, bidon.j+1);
      cout << s << "\n";
      getfem::generic_assembly assem(s);
      assem.push_mi(mim);
      assem.push_mf(mf);
      assem.push_nonlinear_term(&bidon);
      assem.push_vec(V1);
      assem.push_vec(V2);
      assem.assembly();
      gmm::add(gmm::scaled(V2,-1.),V1);
      scalar_type err = gmm::vect_norm2(V1);
      cout << "i=" << bidon.i << ", j=" << bidon.j << " |V1-V2| = " << err << "\n";
      assert(err < 1e-10);      
    }
  }
}

void test_vectorfem(const getfem::mesh_im &mim) {
  cout << "test_vectorfem\n";
  assert(mim.linked_mesh().dim() == 2);
  getfem::mesh_fem mf(mim.linked_mesh(), 6);
  getfem::mesh_fem mf0(mim.linked_mesh(), 2);
  getfem::pfem pf = getfem::fem_descriptor("FEM_RT0(2)");
  cout << "target_dim = " << int(pf->target_dim()) << "\n";
  mf.set_finite_element(pf);
  mf0.set_finite_element(pf);
  cout << "nb_dof = " << mf.nb_dof() << " =" << mf0.nb_dof() << "*3\n";
  assert(mf0.nb_dof()*3 == mf.nb_dof());
  {
    getfem::generic_assembly assem("t=comp(vBase(#1)); print t; print comp(vBase(#1).vBase(#1))(:,i,:,i)");
    assem.push_mi(mim);
    assem.push_mf(mf);
    assem.assembly();
  }
}

void test_vectorfem2() {
  cout << "\n----------------------------------------\ntest_vectorfem2\n\n";
  getfem::mesh m; 
  std::vector<size_type> nsubdiv(2); nsubdiv[0] = nsubdiv[1] = 2;
  regular_unit_mesh(m, nsubdiv, 
		    bgeot::geometric_trans_descriptor("GT_QK(2,1)"), false);
  getfem::mesh_im mim(m);
  mim.set_integration_method(m.convex_index(), 
			     getfem::int_method_descriptor("IM_QUAD(9)"));
  assert(mim.linked_mesh().dim() == 2);
  getfem::mesh_fem mf(mim.linked_mesh(), 6);
  getfem::mesh_fem mf0(mim.linked_mesh(), 2);
  getfem::pfem pf = getfem::fem_descriptor("FEM_RT0Q(2)");
  cout << "target_dim = " << int(pf->target_dim()) << "\n";
  mf.set_finite_element(pf);
  mf0.set_finite_element(pf);
  cout << "nb_dof = " << mf.nb_dof() << " =" << mf0.nb_dof() << "*3\n";
  assert(mf0.nb_dof()*3 == mf.nb_dof());
  {
    getfem::generic_assembly assem("t=comp(vBase(#1)); print t; print comp(vBase(#1).vBase(#1))(:,i,:,i)");
    assem.push_mi(mim);
    assem.push_mf(mf);
    assem.assembly();
  }
  //exit(1);
}

void test_matrixfem(const getfem::mesh_im &mim) {
  cout << "test_matrixfem\n";
  assert(mim.linked_mesh().dim() == 2);

  getfem::mesh_fem mf(mim.linked_mesh()); 
  mf.set_qdim_mn(3, 2);
  getfem::mesh_fem mf0(mim.linked_mesh(), 1);
  getfem::pfem pf = getfem::fem_descriptor("FEM_PK(2,1)");
  cout << "target_dim = " << int(pf->target_dim()) << "\n";
  mf.set_finite_element(pf);
  mf0.set_finite_element(pf);
  cout << "nb_dof = " << mf.nb_dof() << " =" << mf0.nb_dof() << "*6\n";
  assert(mf0.nb_dof()*6 == mf.nb_dof());
  {
    getfem::generic_assembly assem("t=comp(mBase(#1)); print t;");
    assem.push_mi(mim);
    assem.push_mf(mf);
    assem.assembly();
  }

  pf = getfem::fem_descriptor("FEM_RT0(2)");
  cout << "target_dim = " << int(pf->target_dim()) << "\n";
  mf.set_finite_element(pf);
  mf0.set_qdim(2);
  mf0.set_finite_element(pf);
  cout << "nb_dof = " << mf.nb_dof() << " =" << mf0.nb_dof() << "*3\n";
  assert(mf0.nb_dof()*3 == mf.nb_dof());
  {
    getfem::generic_assembly assem("t=comp(mBase(#1)); print t;");
    assem.push_mi(mim);
    assem.push_mf(mf);
    assem.assembly();
  }
  {
    mf.set_qdim_mn(2,2);
    sparse_matrix_type A(mf.nb_dof(), mf.nb_dof());
    getfem::generic_assembly assem("M(#1,#1)+=comp(mBase(#1).mBase(#1))(:,i,j,:,i,j);");
    assem.push_mi(mim);
    assem.push_mf(mf);
    assem.push_mat(A);
    assem.assembly();
    cout << "A = " << A << "\n";
    //exit(1);
  }
}





void inline_red_test(const getfem::mesh_im &mim, getfem::mesh_fem &mf1_, getfem::mesh_fem &mf2) {
  std::stringstream ss; mf1_.write_to_file(ss);
  getfem::mesh_fem mf1(mf1_.linked_mesh()); mf1.read_from_file(ss);

  if (mf1_.convex_index().is_in(2))
    mf1.set_finite_element(2, getfem::fem_descriptor("FEM_PK(2,1)"));

  std::vector<scalar_type> U(mf1.nb_dof()); gmm::fill_random(U);
  std::vector<scalar_type> V(mf2.nb_dof()); gmm::fill_random(V);
  getfem::generic_assembly assem;    
  cout << "INLINE RED\n";
  assem.set("u=data(#1);v=data$2(#2);"
            "V()+=u(i).v(j).comp(Grad(#1)(:,d).Grad(#2)(:,d))(i,j);"); //print comp(Grad(#1)(:,d).Grad(#2)(:,d))");
  assem.push_mi(mim);
  assem.push_mf(mf1);
  assem.push_mf(mf2);
  assem.push_data(U);
  assem.push_data(V);
  std::vector<scalar_type> v1(1);
  assem.push_vec(v1);
  assem.assembly();
  
  {
    cout << "OLD SCHOOL\n";
    getfem::generic_assembly assem2;
    assem2.set("u=data(#1);v=data$2(#2);"
	       "V()+=u(i).v(j).comp(Grad(#1).Grad(#2))(i,d,j,d);"); //print comp(Grad(#1).Grad(#2))(:,d,:,d)");
    assem2.push_mi(mim);
    assem2.push_mf(mf1);
    assem2.push_mf(mf2);
    assem2.push_data(U);
    assem2.push_data(V);
    std::vector<scalar_type> v2(1);
    assem2.push_vec(v2);
    assem2.assembly();



    cout << "v1 = " << v1 << ", v2 = " << v2 << endl;
    assert(gmm::abs(v1[0]-v2[0]) < 1e-14);
  }
  {
    cout << "INLINE RED2\n";
    getfem::generic_assembly assem3;
    mf2.set_qdim(1);
    mf1.set_qdim(1);
    U.resize(mf1.nb_dof());
    V.resize(mf2.nb_dof());
    assem3.set("u=data(#1);v=data$2(#2);"
	       //"V()+=comp(vGrad(#1)(i,j,k).u(i));");
	       "V()+=comp(vGrad(#1)(i,k,:).vGrad(#2)(j,k,:).v(j).u(i))(d,d);");
    /*
      assem3.set("u=data(#1);"
      "t=comp(vGrad(#1)(k,:,:).vGrad(#1)(l,:,:).vGrad(#2).u(k).u(l));"
      "V()+=t(i,j,k,l,m,n,o);");
    */
    assem3.push_mi(mim);
    assem3.push_mf(mf1);
    assem3.push_mf(mf2);
    assem3.push_data(U);
    assem3.push_data(V);
    std::vector<scalar_type> v3(1);
    assem3.push_vec(v3);
    assem3.assembly();
    mf1.set_qdim(1);
    mf2.set_qdim(1);
    
    
    cout << "v1 = " << v1 << ", v3 = " << v3 << endl;

    mf1.write_to_file(std::cerr);
    
    assert(gmm::abs(v1[0]-v3[0]) < 1e-14);
  }
}

template<typename VECT1> class shape_der_nonlinear_term 
  : public getfem::nonlinear_elem_term {
  
  const getfem::mesh_fem &mf;
  const VECT1 &U;
  size_type N;
  base_vector coeff;
  base_matrix gradU, E, Sigma;
  bgeot::multi_index sizes_;
  scalar_type lambda, mu;
  
public:
  shape_der_nonlinear_term(const getfem::mesh_fem &mf_, const VECT1 &U_,
			  scalar_type lambda_, scalar_type mu_) 
    : mf(mf_), U(U_),
      N(mf_.get_qdim()),
      gradU(N, N), E(N, N), Sigma(N,N), sizes_(N,N),
      lambda(lambda_), mu(mu_) { }
  
  const bgeot::multi_index &sizes() const { return sizes_; }
  
  virtual void compute(getfem::fem_interpolation_context& ,
		       bgeot::base_tensor &t) {
    assert(t.size() == N*N);
    /*size_type cv = ctx.convex_num();
    coeff.resize(mf.nb_basic_dof_of_element(cv));
    gmm::copy(gmm::sub_vector(U, gmm::sub_index(mf.ind_basic_dof_of_element(cv))),
	      coeff);
    ctx.pf()->interpolation_grad(ctx, coeff, gradU, mf.get_qdim());
    gmm::copy(gradU, E); gmm::add(gmm::transposed(gradU), E);
    gmm::scale(E, 0.5);
    gmm::copy(gmm::identity_matrix(), Sigma);
    gmm::scale(Sigma, lambda * gmm::mat_trace(E));
    gmm::add(gmm::scaled(E, 2.*mu), Sigma);
    
    for (size_type i = 0; i < N; ++i) 
      for (size_type j = 0; j < N; ++j) {
	t(i,j) = 0.0;
	for (size_type k = 0; k < N; ++k)
	  t(i,j) += Sigma(i,k) * gradU(k,j); 
      }
    */
    for (size_type i = 0; i < N; ++i) 
      for (size_type j = 0; j < N; ++j)
	t(i,j) = 0.0;
    
  }
};

void testbug() {
  std::vector<size_type> nsubdiv(3); nsubdiv[0] = nsubdiv[1] = nsubdiv[2] = 3;
  getfem::mesh m; 
  getfem::regular_unit_mesh(m, nsubdiv, bgeot::simplex_geotrans(3,1));
  getfem::mesh_fem mf1(m,3), mf2(m,3);
  mf1.set_classical_finite_element(m.convex_index(), 1);
  mf2.set_classical_finite_element(m.convex_index(), 1);
  /*mf1.set_finite_element(12, getfem::fem_descriptor("FEM_PK(3,2)"));
    mf2.set_finite_element(15, getfem::fem_descriptor("FEM_PK(3,2)"));*/
  getfem::mesh_im mim(m); mim.set_integration_method(m.convex_index(), 5);
  std::vector<scalar_type> U(mf1.nb_dof()), SD(mf2.nb_dof());
  gmm::fill_random(U);

  shape_der_nonlinear_term<std::vector<scalar_type> > nl(mf1, U, 0, 1);
  
  // trigers a real bug: printing an empty (because of the "vectorization" of vBase)
  // subtensor will crash
  getfem::generic_assembly assem2
    ("t=comp(vBase(#1).vBase(#2));"
     "print(t(:,:,2,3)); ");

  

  //"V(#2) += t(:,:,2,3)"); //0.5*t(i,i,:,j,j) - t(i,j,:,j,i);");
  assem2.push_mi(mim);
  assem2.push_mf(mf1);
  assem2.push_nonlinear_term(&nl);
  assem2.push_mf(mf2);
  assem2.push_vec(SD);
  
  double t0 = dal::uclock_sec();
  assem2.assembly();
  cerr << " done : " << dal::uclock_sec() - t0 << "\n"; exit(1);
  exit(1);
}

void test_gradgt(const getfem::mesh_im &mim, const getfem::mesh_fem &mf1) {
  std::vector<scalar_type> U(mf1.nb_dof()); gmm::fill_random(U);
  getfem::generic_assembly assem;    
  assem.set(//"u=data(#1);"
            "V()+=comp()"); //Grad(#1)(:,d).GradGT()(d,:))(i,:);");
  assem.push_mi(mim);
  //assem.push_mf(mf1);
  //assem.push_mf(mf2);
  assem.push_data(U);
  std::vector<scalar_type> v1(1);
  assem.push_vec(v1);
  assem.assembly();
  scalar_type vref=v1[0];
  v1[0]=0;
  
  getfem::generic_assembly assem2;    

  assem2.set("V()+=comp(GradGT().GradGTInv())(i,k,k,j);"); // print comp(GradGT()); print comp(GradGTInv()); ");
  assem2.push_mi(mim);
  assem2.push_vec(v1);
  assem2.assembly();
  cout << "test_gradgt: V1=" << v1[0] << " ==?== " << vref << "\n";
  assert(std::abs(v1[0]-vref*mim.linked_mesh().dim()) < 1e-6);
}

#endif /* ASSEMBLY_CHECK */

int main(int argc, char *argv[]) {

  GMM_SET_EXCEPTION_DEBUG; // Exceptions make a memory fault, to debug.
  FE_ENABLE_EXCEPT;        // Enable floating point exception for Nan.

  try {

    // getfem::pfem pf = getfem::fem_descriptor("FEM_PK_PRISM_HIERARCHICAL(3,3)");
    

    //testbug();
    do_general_check();

#ifdef ASSEMBLY_CHECK
    bool do_old=true, do_new=true;
    param.init(argc,argv);
    std::vector<bool> tests(NB_TESTS, true);
    if (param.do_what >=0 && param.do_what < NB_TESTS) {
      std::fill(tests.begin(),tests.end(),false);
      tests[param.do_what]=true;
    }


   cerr << "\n\n-----------------------------SIMPLE MESH TESTS---------------------\n\n";
   {
     getfem::mesh m;
     m.add_triangle_by_points(mknode(0.,0.),mknode(1.2,0.),mknode(0.1,1.5));     
     m.add_triangle_by_points(mknode(0.,0.),mknode(-1.2,0.),mknode(0.1,1.5));
     std::vector<base_node> pts;
     pts.push_back(mknode(0,0));
     pts.push_back(mknode(.65,0));
     pts.push_back(mknode(1.2,0));
     pts.push_back(mknode(0,-.3));
     pts.push_back(mknode(.6,-.33));
     pts.push_back(mknode(0.1,-.8));
     m.add_convex_by_points(bgeot::simplex_geotrans(2,2), pts.begin());
     m.region(1).add(0, 0);
     m.region(1).add(0, 1);
     getfem::mesh_fem mf(m), mfne(m);
     classical_mesh_fem(mf, 2);     
     mfne.set_finite_element(getfem::fem_descriptor("FEM_ARGYRIS"));

     getfem::mesh_fem mfq(m), mfqne(m); 
     mfq.set_qdim(m.dim());
     classical_mesh_fem(mfq, 2);
     mfqne.set_qdim(m.dim());
     mfqne.set_finite_element(getfem::fem_descriptor("FEM_ARGYRIS"));
     getfem::mesh_fem mfd(m); 
     mfd.set_classical_finite_element(1);
     getfem::mesh_fem mfdq(m); 
     mfdq.set_classical_finite_element(1);
     mfdq.set_qdim(m.dim());     
     
     getfem::mesh_im mim(m);
     init_mesh_im(mim, true);
     inline_red_test(mim,mf,mfd);
     
     
     inline_red_test(mim,mfne,mfd);

     test_vectorfem(mim);
     test_vectorfem2();
     test_matrixfem(mim);

     test_gradgt(mim,mf);
     run_tests(mim,mf,mfq,mfd,mfdq,do_new,do_old,tests,1,1);
     run_tests(mim,mfne,mfqne,mfd,mfdq,do_new,do_old,tests,1,1);
   }

   cerr << "\n\n-----------------------------PERFORMANCE TESTS---------------------\n\n";   
   {
     getfem::mesh m; 
     gen_mesh(m);
     
     getfem::mesh_fem mf(m); 
     init_mesh_fem(mf,false);

     getfem::mesh_im mim(m);
     init_mesh_im(mim, false);

     getfem::mesh_fem mfq(m); 
     mfq.set_qdim(m.dim());
     init_mesh_fem(mfq,false);

     getfem::mesh_fem mfqne(m);
     init_mesh_fem(mfqne,false);
  
     test_nonlin(mim,mfq);

     getfem::mesh_fem mfd(m); 
     init_mesh_fem(mfd,true);
     
     getfem::mesh_fem mfdq(m); 
     mfdq.set_qdim(m.dim());
     init_mesh_fem(mfdq,true);
     
     //mf.write_to_file("toto1.mf",true);
     //mfq.write_to_file("totoq.mf",true);

     run_tests(mim,mf,mfq,mfd,mfdq,param.do_new,param.do_old,tests,1,1);
   }
#endif /* ASSEMBLY_CHECK */
  }
  GMM_STANDARD_CATCH_ERROR;
  cout << "failures: " << fail_cnt << endl;
  return fail_cnt; 
}
