Beispiel #1
0
/* vector pp of parameters is as follows:
** pp[0]: principal eigenvalue 
** pp[1]: fraction of 1st tensor
** pp[2]: phi for 1st tensor
** pp[3]: phi for 2nd tensor
*/
void
_tenLevmarPeledCB(double *pp, double *xx, int mm, int nn, void *_pvlData) {
  /* char me[]="_tenLevmarPeledCB"; */
  double tenA[7], tenB[7];
  int ii;
  tenDwiGagePvlData *pvlData;
  double *egrad;
 
  AIR_UNUSED(mm);
  pvlData = AIR_CAST(tenDwiGagePvlData *, _pvlData);

  /* Form the tensors using the estimated parms */
  _tenPeledRotate2D(tenA, pp[0], pvlData->ten1Eval[2], pp[2]);
  _tenPeledRotate2D(tenB, pp[0], pvlData->ten1Eval[2], pp[3]);

  egrad = AIR_CAST(double *, pvlData->nten1EigenGrads->data);
  /* skip past b0 gradient, HEY: not general purpose */
  egrad += 3; 
  for (ii=0; ii<nn; ii++) {
    double argA, argB, sigA, sigB;
    argA = -pvlData->tec2->bValue*TEN_T3V_CONTR(tenA, egrad + 3*ii);
    argB = -pvlData->tec2->bValue*TEN_T3V_CONTR(tenB, egrad + 3*ii);
    if (pvlData->levmarUseFastExp) {
      sigA = airFastExp(argA);
      sigB = airFastExp(argB);
    } else {
      sigA = exp(argA);
      sigB = exp(argB);
    }
    xx[ii] = pvlData->tec2->knownB0*(pp[1]*sigA + (1-pp[1])*sigB);
  }
  return;
}
Beispiel #2
0
int
main(int argc, char *argv[]) {
  char *me;
  unsigned int ii, NN;
  double min, max, *out;
  Nrrd *nout;

  me = argv[0];
  if (5 != argc) {
    usage(me);
  }
  if (3 != (sscanf(argv[2], "%u", &NN)
            + sscanf(argv[1], "%lf", &min)
            + sscanf(argv[3], "%lf", &max))) {
    fprintf(stderr, "%s: couldn't parse %s %s %s double uint double",
            me, argv[1], argv[2], argv[3]);
    usage(me);
  }
  nout = nrrdNew();
  if (nrrdAlloc_va(nout, nrrdTypeDouble, 2,
                   AIR_CAST(size_t, 5),
                   AIR_CAST(size_t, NN))) {
    fprintf(stderr, "%s: trouble allocating:\n%s", me,
            biffGetDone(NRRD));
    exit(1);
  }
  out = AIR_CAST(double *, nout->data);
  for (ii=0; ii<NN; ii++) {
    double xx, rr, ff, gg;
    xx = AIR_AFFINE(0, ii, NN-1, min, max);
    rr = exp(xx);
    ff = airFastExp(xx);
    gg = airExp(xx);
    if (rr < 0 || ff < 0 || gg < 0
        || !AIR_EXISTS(rr) || !AIR_EXISTS(ff) || !AIR_EXISTS(gg)) {
      fprintf(stderr, "%s: problem: %f -> real %f, approx %f %f\n",
              me, xx, rr, ff, gg);
      exit(1);
    }
    out[0] = rr;
    out[1] = ff;
    out[2] = (ff-rr)/rr;
    out[3] = gg;
    out[4] = (gg-rr)/rr;
    out += 5;
  }

  if (nrrdSave(argv[4], nout, NULL)) {
    fprintf(stderr, "%s: trouble saving:\n%s", me,
            biffGetDone(NRRD));
    exit(1);
  }
  exit(0);
}
Beispiel #3
0
/*
**  0    1       (2)
** texp  N
*/
int
main(int argc, char *argv[]) {
  char *me;
  unsigned int ii, NN;

  me = argv[0];
  if (2 != argc || 1 != sscanf(argv[1], "%u", &NN)) {
    fprintf(stderr, "%s: need one uint as argument\n", me);
    exit(1);
  }
  for (ii=0; ii<NN; ii++) {
    double xx;
    xx = AIR_AFFINE(0.0, airDrandMT(), 1.0, -10, 10);
    printf("%f %f\n", exp(xx), airFastExp(xx));
  }
  exit(0);
}