OrientedLattice.cpp

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// Mantid Repository : https://github.com/mantidproject/mantid
//
// Copyright © 2018 ISIS Rutherford Appleton Laboratory UKRI,
//   NScD Oak Ridge National Laboratory, European Spallation Source,
//   Institut Laue - Langevin & CSNS, Institute of High Energy Physics, CAS
// SPDX - License - Identifier: GPL - 3.0 +
#include "MantidGeometry/Crystal/OrientedLattice.h"
#include "MantidKernel/Exception.h"
 
namespace Mantid::Geometry {
using Mantid::Kernel::DblMatrix;
using Mantid::Kernel::V3D;
 
namespace {
const double TWO_PI = 2. * M_PI;
}
 
OrientedLattice::OrientedLattice(const DblMatrix &Umatrix) : UnitCell() {
  if (Umatrix.isRotation()) {
    U = Umatrix;
    UB = U * getB();
    ModUB = UB * getModHKL();
  } else
    throw std::invalid_argument("U is not a proper rotation");
}
 
OrientedLattice::OrientedLattice(const double _a, const double _b, const double _c, const DblMatrix &Umatrix)
    : UnitCell(_a, _b, _c) {
  if (Umatrix.isRotation()) {
    U = Umatrix;
    UB = U * getB();
    ModUB = UB * getModHKL();
  } else
    throw std::invalid_argument("U is not a proper rotation");
}
 
OrientedLattice::OrientedLattice(const double _a, const double _b, const double _c, const double _alpha,
                                 const double _beta, const double _gamma, const DblMatrix &Umatrix, const int angleunit)
    : UnitCell(_a, _b, _c, _alpha, _beta, _gamma, angleunit) {
  if (Umatrix.isRotation()) {
    U = Umatrix;
    UB = U * getB();
    ModUB = UB * getModHKL();
  } else
    throw std::invalid_argument("U is not a proper rotation");
}
 
OrientedLattice::OrientedLattice(const UnitCell &uc, const DblMatrix &Umatrix) : UnitCell(uc), U(Umatrix) {
  if (Umatrix.isRotation()) {
    U = Umatrix;
    UB = U * getB();
    ModUB = UB * getModHKL();
  } else
    throw std::invalid_argument("U is not a proper rotation");
}
 
const DblMatrix &OrientedLattice::getU() const { return U; }
 
const DblMatrix &OrientedLattice::getUB() const { return UB; }
 
const DblMatrix &OrientedLattice::getModUB() const { return ModUB; }
 
void OrientedLattice::setU(const DblMatrix &newU, const bool force) {
  // determinant ==1 or (determinant == +/-1 and force)
  if (newU.isRotation() || (force && newU.isOrthogonal())) {
    U = newU;
    UB = U * getB();
    ModUB = UB * getModHKL();
  } else
    throw std::invalid_argument("U is not a proper rotation");
}
 
void OrientedLattice::setUB(const DblMatrix &newUB) {
  // check if determinant is close to 0. The 1e-10 value is arbitrary
  if (std::fabs(newUB.determinant()) > 1e-10) {
    UB = newUB;
    DblMatrix newGstar, B;
    newGstar = newUB.Tprime() * newUB;
    this->recalculateFromGstar(newGstar);
    B = this->getB();
    B.Invert();
    U = newUB * B;
  } else
    throw std::invalid_argument("determinant of UB is too close to 0");
}
 
void OrientedLattice::setModUB(const DblMatrix &newModUB) {
  ModUB = newModUB;
  DblMatrix UBinv, newModHKL;
  UBinv = getUB();
  UBinv.Invert();
  newModHKL = UBinv * ModUB;
  setModHKL(newModHKL);
}
 
V3D OrientedLattice::hklFromQ(const V3D &Q) const {
  DblMatrix UBinv = this->getUB();
  UBinv.Invert();
  V3D out = UBinv * Q / TWO_PI; // transform back to HKL
  return out;
}
 
V3D OrientedLattice::qFromHKL(const V3D &hkl) const { return UB * hkl * TWO_PI; }
 
Kernel::V3D OrientedLattice::getuVector() const {
  V3D z(0, 0, 1);
  DblMatrix UBinv = UB;
  UBinv.Invert();
  return UBinv * z;
}
 
Kernel::V3D OrientedLattice::getvVector() const {
  V3D x(1, 0, 0);
  DblMatrix UBinv = UB;
  UBinv.Invert();
  return UBinv * x;
}
 
const DblMatrix &OrientedLattice::setUFromVectors(const V3D &u, const V3D &v) {
  const DblMatrix &BMatrix = this->getB();
  V3D buVec = BMatrix * u;
  V3D bvVec = BMatrix * v;
  // try to make an orthonormal system
  if (buVec.norm2() < 1e-10)
    throw std::invalid_argument("|B.u|~0");
  if (bvVec.norm2() < 1e-10)
    throw std::invalid_argument("|B.v|~0");
  buVec.normalize(); // 1st unit vector, along Bu
  V3D bwVec = buVec.cross_prod(bvVec);
  const auto norm = bwVec.norm();
  if (norm < 1e-5) {
    // 3rd unit vector, perpendicular to Bu,Bv
    throw std::invalid_argument("u and v are parallel");
  }
  bwVec /= norm;
  // 2nd unit vector, perpendicular to Bu, in the Bu,Bv plane
  bvVec = bwVec.cross_prod(buVec);
  DblMatrix tau(3, 3), lab(3, 3), U(3, 3);
  /*lab      = U tau
   / 0 1 0 \     /bu[0] bv[0] bw[0]\
   | 0 0 1 | = U |bu[1] bv[1] bw[1]|
   \ 1 0 0 /     \bu[2] bv[2] bw[2]/
   */
  lab[0][1] = 1.;
  lab[1][2] = 1.;
  lab[2][0] = 1.;
  tau[0][0] = buVec[0];
  tau[0][1] = bvVec[0];
  tau[0][2] = bwVec[0];
  tau[1][0] = buVec[1];
  tau[1][1] = bvVec[1];
  tau[1][2] = bwVec[1];
  tau[2][0] = buVec[2];
  tau[2][1] = bvVec[2];
  tau[2][2] = bwVec[2];
  tau.Invert();
  U = lab * tau;
  this->setU(U);
  return getU();
}
 
void OrientedLattice::saveNexus(::NeXus::File *file, const std::string &group) const {
  file->makeGroup(group, "NXcrystal", true);
  file->writeData("unit_cell_a", this->a());
  file->writeData("unit_cell_b", this->b());
  file->writeData("unit_cell_c", this->c());
  file->writeData("unit_cell_alpha", this->alpha());
  file->writeData("unit_cell_beta", this->beta());
  file->writeData("unit_cell_gamma", this->gamma());
  // Save the UB matrix
  std::vector<double> ub = this->UB.getVector();
  std::vector<int> dims(2, 3); // 3x3 matrix
  file->writeData("orientation_matrix", ub, dims);
 
  file->closeGroup();
}
 
void OrientedLattice::loadNexus(::NeXus::File *file, const std::string &group) {
  file->openGroup(group, "NXcrystal");
  std::vector<double> ub;
  file->readData("orientation_matrix", ub);
  // Turn into a matrix
  DblMatrix ubMat(ub);
  // This will set the lattice parameters and the U matrix:
  this->setUB(ubMat);
  file->closeGroup();
}
 
bool OrientedLattice::GetUB(DblMatrix &UB, const V3D &a_dir, const V3D &b_dir, const V3D &c_dir) {
  if (UB.numRows() != 3 || UB.numCols() != 3) {
    throw std::invalid_argument("Find_UB(): UB matrix NULL or not 3X3");
  }
 
  UB.setRow(0, a_dir);
  UB.setRow(1, b_dir);
  UB.setRow(2, c_dir);
  try {
    UB.Invert();
  } catch (...) {
    return false;
  }
  return true;
}
 
bool OrientedLattice::GetABC(const DblMatrix &UB, V3D &a_dir, V3D &b_dir, V3D &c_dir) {
  if (UB.numRows() != 3 || UB.numCols() != 3) {
    throw std::invalid_argument("GetABC(): UB matrix NULL or not 3X3");
  }
 
  DblMatrix UB_inverse(UB);
  try {
    UB_inverse.Invert();
  } catch (...) {
    return false;
  }
  a_dir(UB_inverse[0][0], UB_inverse[0][1], UB_inverse[0][2]);
  b_dir(UB_inverse[1][0], UB_inverse[1][1], UB_inverse[1][2]);
  c_dir(UB_inverse[2][0], UB_inverse[2][1], UB_inverse[2][2]);
 
  return true;
}
void OrientedLattice::recalculate() {
  UnitCell::recalculate();
  UB = U * getB();
}
bool OrientedLattice::operator==(const OrientedLattice &other) const { return UB == other.UB; }
bool OrientedLattice::operator!=(const OrientedLattice &other) const { return UB != other.UB; }
} // namespace Mantid::Geometry