Esempio n. 1
0
main()
{
	int i,j,n=N,info;
	float **aa; 
	
	aa = alloc2float(n,n);
	for (i=0; i<n; i++)
		for (j=0; j<n; j++)
			aa[i][j] = 0.0;
	
	for (i=0; i<n; i++) {
		aa[i][i] = b[i] = 10*(i+1);
		if (i>0) aa[i][i-1] = c[i-1] = i-1;
		if (i<n-1) aa[i][i+1] = a[i+1] = i+1;
		x[i] = r[i] = i;
	}

	sgefa(aa,n,ipvt,&info);
	sgesl(aa,n,ipvt,x,0);
	
	tridif(n,a,b,c,r,u);
	
	for (i=0; i<n; i++)
		printf("x[%d] = %g  u[%d] = %g\n",i,x[i],i,u[i]);
}
Esempio n. 2
0
int volt_step(double *y, double t, double dt, int neq, double *yg, double *yp,
              double *yp2, double *ytemp, double *errvec, double *jac) {
  int i0, iend, ishift, i, iter = 0, info, ipivot[MAXODE1], j, ind;
  int n1 = NODE + 1;
  double dt2 = .5 * dt, err;
  double del, yold, fac, delinv;
  i0 = MAX(0, CurrentPoint - MaxPoints);
  iend = MIN(CurrentPoint - 1, MaxPoints - 1);
  ishift = i0 % MaxPoints;
  init_sums(T0, CurrentPoint, dt, i0, iend,
            ishift); /*  initialize all the sums */
  KnFlag = 0;
  for (i = 0; i < neq; i++) {
    set_ivar(i + 1, y[i]);
    yg[i] = y[i];
  }
  for (i = NODE; i < NODE + NMarkov; i++)
    set_ivar(i + 1 + FIX_VAR, y[i]);
  set_ivar(0, t - dt);
  for (i = NODE; i < NODE + FIX_VAR; i++)
    set_ivar(i + 1, evaluate(my_ode[i]));
  for (i = 0; i < NODE; i++) {
    if (!EqType[i])
      yp2[i] = y[i] + dt2 * evaluate(my_ode[i]);
    else
      yp2[i] = 0.0;
  }
  KnFlag = 1;
  while (1) {
    get_kn(yg, t);
    for (i = NODE; i < NODE + FIX_VAR; i++)
      set_ivar(i + 1, evaluate(my_ode[i]));
    for (i = 0; i < NODE; i++) {
      yp[i] = evaluate(my_ode[i]);
      /*  plintf(" yp[%d]=%g\n",i,yp[i]); */
      if (EqType[i])
        errvec[i] = -yg[i] + yp[i];
      else
        errvec[i] = -yg[i] + dt2 * yp[i] + yp2[i];
    }
    /*   Compute Jacobian     */
    for (i = 0; i < NODE; i++) {
      del = NEWT_ERR * MAX(NEWT_ERR, fabs(yg[i]));
      yold = yg[i];
      yg[i] += del;
      delinv = 1. / del;
      get_kn(yg, t);
      for (j = NODE; j < NODE + FIX_VAR; j++)
        set_ivar(j + 1, evaluate(my_ode[j]));
      for (j = 0; j < NODE; j++) {
        fac = delinv;
        if (!EqType[j])
          fac *= dt2;
        jac[j * NODE + i] = (evaluate(my_ode[j]) - yp[j]) * fac;
      }
      yg[i] = yold;
    }

    for (i = 0; i < NODE; i++)
      jac[n1 * i] -= 1.0;
    sgefa(jac, NODE, NODE, ipivot, &info);
    if (info != -1) {

      return (-1); /* Jacobian is singular   */
    }
    err = 0.0;
    sgesl(jac, NODE, NODE, ipivot, errvec, 0);
    for (i = 0; i < NODE; i++) {
      err = MAX(fabs(errvec[i]), err);
      yg[i] -= errvec[i];
    }
    if (err < EulTol)
      break;
    iter++;
    if (iter > MaxEulIter)
      return (-2); /* too many iterates   */
  }
  /* We have a good point; lets save it    */
  get_kn(yg, t);
  /*  for(i=NODE;i<NODE+FIX_VAR;i++)
     set_ivar(i+1,evaluate(my_ode[i])); */
  for (i = 0; i < NODE; i++)
    y[i] = yg[i];
  ind = CurrentPoint % MaxPoints;
  for (i = 0; i < NODE + FIX_VAR + NMarkov; i++)
    Memory[i][ind] = get_ivar(i + 1);
  CurrentPoint++;

  return (0);
}
Esempio n. 3
0
void bvshoot(double *y, double *yend, double err, double eps, int maxit,
             int *iret, int n, int ishow, int iper, int ipar, int ivar,
             double sect) {
  double *jac, *f, *fdev, *y0, *y1;
  double dev, error, ytemp;

  int ntot = n;
  int i, istart = 1, j;
  int ipvt[MAXODE1];
  char esc;
  int info, niter = 0;
  double dt = DELTA_T, t;
  double t0 = T0;
  double t1 = T0 + TEND * dt / fabs(dt);

  if (iper)
    ntot = n + 1;
  jac = (double *)malloc(ntot * ntot * sizeof(double));
  f = (double *)malloc(ntot * sizeof(double));
  fdev = (double *)malloc(ntot * sizeof(double));
  y0 = (double *)malloc(ntot * sizeof(double));
  y1 = (double *)malloc(ntot * sizeof(double));

  for (i = 0; i < n; i++)
    y0[i] = y[i];
  if (iper)
    get_val(upar_names[ipar], &y0[n]);

  /* dt=(t1-t0)/nt;  */
  while (1) {
    esc = my_abort();

    {

      if (esc == ESC) {
        *iret = ABORT;
        break;
      }
      if (esc == '/') {
        *iret = ABORT_ALL;
        break;
      }
    }

    t = t0;
    istart = 1;
    if (iper)
      set_val(upar_names[ipar], y0[n]);

    if (ishow) {
      integrate(&t, y, TEND, DELTA_T, 1, NJMP, &istart);
    } else {
      if (ode_int(y, &t, &istart) == 0) {
        *iret = -4;
        goto bye;
      }
    }
    for (i = 0; i < n; i++) {
      y1[i] = y[i];
      /*  plintf("%f \n",y[i]); */
    }

    do_bc(y0, t0, y1, t1, f, n);
    if (iper)
      f[n] = y1[ivar] - sect;
    error = 0.0;
    for (i = 0; i < ntot; i++)
      error += fabs(f[i]);
    if (error < err) {
      for (i = 0; i < n; i++)
        y[i] = y0[i]; /*   Good values .... */
      if (iper) {
        set_val(upar_names[ipar], y0[n]);
        redraw_params();
      }

      for (i = 0; i < n; i++)
        yend[i] = y1[i];
      *iret = GOODSHOT;
      goto bye;
    }
    /* plintf("err1 = %f tol= %f \n",error,err); */
    niter++;
    if (niter > maxit) {
      *iret = -2;
      goto bye;
    } /* Too many iterates   */

    /*   create the Jacobian matrix ...   */

    for (j = 0; j < ntot; j++) {
      for (i = 0; i < n; i++)
        y[i] = y0[i];
      if (fabs(y0[j]) < eps)
        dev = eps * eps;
      else
        dev = eps * fabs(y0[j]);

      if (j < n)
        y[j] = y[j] + dev;
      ytemp = y0[j];
      y0[j] = y0[j] + dev;

      if (j == n)
        set_val(upar_names[ipar], y0[j]);

      t = t0;
      istart = 1;

      if (ode_int(y, &t, &istart) == 0) {
        *iret = -4;
        goto bye;
      }

      do_bc(y0, t0, y, t1, fdev, n);
      if (iper)
        fdev[n] = y[ivar] - sect;
      y0[j] = ytemp;
      for (i = 0; i < ntot; i++)
        jac[j + i * ntot] = (fdev[i] - f[i]) / dev;
    }

    sgefa(jac, ntot, ntot, ipvt, &info);
    if (info != -1) {
      *iret = -3;
      goto bye;
    }
    for (i = 0; i < ntot; i++)
      fdev[i] = f[i];
    sgesl(jac, ntot, ntot, ipvt, fdev, 0);
    error = 0.0;
    for (i = 0; i < ntot; i++) {
      y0[i] = y0[i] - fdev[i];
      error += fabs(fdev[i]);
    }

    for (i = 0; i < n; i++)
      y[i] = y0[i];
    /* plintf("error2 = %f \n",error);  */
    if (error < 1.e-10) {
      for (i = 0; i < n; i++)
        yend[i] = y1[i];
      *iret = 2;
      goto bye;
    }
  }

bye:

  free(f);
  free(y1);
  free(y0);
  free(jac);
  free(fdev);
}
Esempio n. 4
0
File: sgefa.c Progetto: 8l/insieme
void test03 ( int n )

/******************************************************************************/
/*
  Purpose:

    TEST03 runs the revised version of SGEFA in sequential mode.

  Modified:

    07 April 2008

  Author:

    John Burkardt
*/
{
  float *a;
  float *b;
  float err;
  int i;
  int info;
  int *ipvt;
  int job;
  int lda;
  double wtime;
  float *x;
/*
  Generate the linear system A * x = b.
*/
  lda = n;
  a = ( float * ) malloc ( lda * n * sizeof ( float ) );
  b = ( float * ) malloc ( n * sizeof ( float ) );
  x = ( float * ) malloc ( n * sizeof ( float ) );

  matgen ( lda, n, a, x, b );
/*
  Factor the linear system.
*/
  ipvt = ( int * ) malloc ( n * sizeof ( int ) );

  wtime = omp_get_wtime ( );
  info = msgefa2 ( a, lda, n, ipvt );
  wtime = omp_get_wtime ( ) - wtime;

  if ( info != 0 )
  {
    printf ( "\n" );
    printf ( "TEST03 - Fatal error!\n" );
    printf ( "  MSGEFA2 reports the matrix is singular.\n" );
    exit ( 1 );
  }
/*
  Solve the linear system.
*/
  job = 0;
  sgesl ( a, lda, n, ipvt, b, job );

  err = 0.0;
  for ( i = 0; i < n; i++ )
  {
    err = err + fabs ( x[i] - b[i] );
  }

  printf ( "  Revised   Sequential   %8d  %10.4e  \n", n, err );

  free ( a );
  free ( b );
  free ( ipvt );
  free ( x );

  return;
}