Files
Jungfraujoch/tests/MolecularReplacementTest.cpp
T
leonarski_fandClaude Opus 5.5 30c7bee15f rugnux: --af-model becomes --mr, for predictions and experimental structures alike
- The option is --mr <file>. What kind of model it is is read from the file: a prediction where it
  is ModelCIF (_ma_qa_metric) or has no cell and one B value per residue in 0-100 (AlphaFold PDB/mmCIF);
  an experimental structure otherwise. A prediction is handled as before (pLDDT >= 70 trim, B from
  pLDDT, PAE domains where the AlphaFold DB's PAE file sits beside it). An experimental structure is
  taken as its polymer - no waters, ligands, hydrogens or alternative conformers, occupancy 1, isotropic
  B as refined - with a coordinate error of 0.67 A (a prediction's at pLDDT 90) for sigma_A; a B column
  above 100 no longer stops the search.
- The report section is MOLECULAR REPLACEMENT (EXPERIMENTAL), its keys MR_* (MR, MR_MODEL_FILE,
  MR_MODEL_KIND, MR_DECISION, MR_SPACE_GROUP, MR_COPIES, MR_HAND_CHECK, MR_SECONDS, ...); the <prefix>_mr
  outputs are unchanged.
- The twin hypothesis' merge that is made only for the model to test (a metric re-ask promoted the
  indexed lattice's group) is written and reported only where the model chooses the subgroup.

Raw deposited coordinates of nine control sets, unconverted: every one placed and confirmed against the
deposition (all chains as one body), the groups the same as with the prediction or the prepared model.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01EizBKhTqrAYago9KJG3dA3
2026-10-12 19:30:22 +02:00

513 lines
25 KiB
C++

// SPDX-FileCopyrightText: 2026 Filip Leonarski, Paul Scherrer Institute <filip.leonarski@psi.ch>
// SPDX-License-Identifier: GPL-3.0-only
#include <catch2/catch_all.hpp>
#include <cmath>
#include <cstdio>
#include <fstream>
#include <random>
#include <gemmi/dencalc.hpp>
#include <gemmi/it92.hpp>
#include "../image_analysis/structure_refinement/ModelFFT.h"
#include "../image_analysis/structure_refinement/MolecularReplacement.h"
#include "../image_analysis/structure_refinement/RigidBodyRefine.h"
#include "../common/Logger.h"
#ifdef JFJOCH_USE_CUDA
#include "../common/CUDAWrapper.h"
#include "../image_analysis/structure_refinement/MolecularReplacementGPU.h"
#include "../image_analysis/structure_refinement/RigidBodyGPU.h"
#endif
namespace {
// A synthetic body: carbon atoms scattered in a 12 A sphere, centroid at the origin.
SearchModel synthetic_model() {
SearchModel m;
std::mt19937 rng(7);
std::uniform_real_distribution<double> u(-12.0, 12.0);
gemmi::Model model(1);
gemmi::Chain chain("A");
gemmi::Residue res;
res.name = "UNK";
res.seqid = gemmi::SeqId(1, ' ');
std::vector<gemmi::Vec3> pos;
while (pos.size() < 300) {
const gemmi::Vec3 p(u(rng), u(rng), u(rng));
if (p.length() < 12.0)
pos.push_back(p);
}
gemmi::Vec3 c;
for (const auto &p : pos)
c += p;
c *= 1.0 / pos.size();
for (const auto &p : pos) {
gemmi::Atom a;
a.name = "CA"; // every atom counts in the clash check
a.element = gemmi::El::C;
a.pos = gemmi::Position(p - c);
a.b_iso = 15.0f;
a.occ = 1.0f;
res.atoms.push_back(a);
m.radius_A = std::max(m.radius_A, (p - c).length());
}
chain.residues.push_back(res);
model.chains.push_back(chain);
m.st.models.push_back(model);
m.residues_read = m.residues_kept = 1;
m.mass_da = 3600;
return m;
}
gemmi::Mat33 axis_angle(gemmi::Vec3 axis, double deg) {
axis = axis.normalized();
const double k = deg * M_PI / 180.0, s = std::sin(k), c1 = 1.0 - std::cos(k);
const double x = axis.x, y = axis.y, z = axis.z;
return {1 + c1 * (x * x - 1), -s * z + c1 * x * y, s * y + c1 * x * z,
s * z + c1 * x * y, 1 + c1 * (y * y - 1), -s * x + c1 * y * z,
-s * y + c1 * x * z, s * x + c1 * y * z, 1 + c1 * (z * z - 1)};
}
// |F|^2 of the placed crystal to 4 A, as merged reflections.
std::vector<MergedReflection> observed(const gemmi::Structure &crystal) {
gemmi::DensityCalculator<gemmi::IT92<float>, float> dc;
dc.d_min = 3.5;
dc.rate = 1.5;
dc.set_grid_cell_and_spacegroup(crystal);
dc.put_model_density_on_grid(crystal.models[0]);
const auto f = MapToFPhi(dc.grid).prepare_asu_data(3.5, 0, false, false, false);
std::vector<MergedReflection> out;
for (const auto &hv : f.v) {
MergedReflection r;
r.h = hv.hkl[0];
r.k = hv.hkl[1];
r.l = hv.hkl[2];
r.I = std::norm(hv.value);
r.sigma = 1;
r.F = std::abs(hv.value);
r.d = 1.0 / std::sqrt(crystal.cell.calculate_1_d2(hv.hkl));
out.push_back(r);
}
return out;
}
}
TEST_CASE("MolecularReplacement_UniformRotationsCoverSO3", "[MolecularReplacement]") {
const auto rotations = UniformRotations(6.0);
const double step = 6.0 * M_PI / 180.0;
// 8 pi^2 is the volume of SO(3) in the measure a 6 deg cube of Euler-like angles samples.
const double expected = 8 * M_PI * M_PI / (step * step * step);
CHECK(rotations.size() > 0.8 * expected);
CHECK(rotations.size() < 1.2 * expected);
// Every rotation has a sampled one nearby.
std::mt19937 rng(11);
std::normal_distribution<double> g;
const std::vector<gemmi::Mat33> identity{gemmi::Mat33()};
double worst = 0;
for (int i = 0; i < 100; i++) {
const gemmi::Mat33 r = axis_angle({g(rng), g(rng), g(rng)}, std::uniform_real_distribution<double>(0, 180)(rng));
double best = 180;
for (const auto &s : rotations)
best = std::min(best, RotationDistanceDeg(r, s, identity));
worst = std::max(worst, best);
}
CHECK(worst < 6.0);
}
TEST_CASE("MolecularReplacement_RotationAsu", "[MolecularReplacement]") {
const gemmi::UnitCell cell(40, 40, 60, 90, 90, 90);
const auto pg = CartesianPointGroup(gemmi::get_spacegroup_by_name("P 41 2 2"), cell);
REQUIRE(pg.size() == 8);
const auto all = UniformRotations(10.0);
const auto asu = RotationAsu(all, pg);
// One class in eight, give or take the boundaries.
CHECK(asu.size() > all.size() / 8 * 0.9);
CHECK(asu.size() < all.size() / 8 * 1.3);
// Every sampled rotation has a class member in the ASU close by.
for (size_t i = 0; i < all.size(); i += 37) {
double best = 180;
for (const auto &s : asu)
best = std::min(best, RotationDistanceDeg(s, all[i], pg));
CHECK(best < 10.0);
}
}
TEST_CASE("MolecularReplacement_SameRotationGroups", "[MolecularReplacement]") {
const auto groups = SameRotationGroups(gemmi::get_spacegroup_by_name("P 41"));
REQUIRE(groups.size() == 4);
CHECK(groups[0].xhm() == "P 41");
const auto i = SameRotationGroups(gemmi::get_spacegroup_by_name("I 41 2 2"));
CHECK(i.size() == 2); // I 4 2 2, I 41 2 2
// Each group once, not again on another origin: P 2 2 2, P 2 2 21 in three settings, P 21 21 2 in
// three, P 21 21 21.
CHECK(SameRotationGroups(gemmi::get_spacegroup_by_name("P 21 21 2")).size() == 8);
CHECK(SameRotationGroups(gemmi::get_spacegroup_by_name("I 2 2 2")).size() == 2);
CHECK(SameRotationGroups(gemmi::get_spacegroup_by_name("P 42 21 2")).size() == 8);
}
TEST_CASE("MolecularReplacement_SyntheticPlacement", "[MolecularReplacement]") {
const SearchModel model = synthetic_model();
const gemmi::UnitCell cell(42, 50, 58, 90, 90, 90);
const gemmi::SpaceGroup &sg = gemmi::get_spacegroup_by_name("P 21 21 21");
const gemmi::Mat33 truth = axis_angle({1, 2, 3}, 50);
const gemmi::Fractional t(0.17, 0.31, 0.09);
const gemmi::Structure crystal = PlaceSearchModel(model, truth, t, cell, sg);
const auto merged = observed(crystal);
const SearchReflections refl = MakeSearchReflections(merged, cell, sg, 4.0, 12.0);
REQUIRE(refl.hkl.size() > 300);
const MolecularTransform ft(model, 4.0, 4);
// The rotation function's best orientation is the true one, to the sampling.
const auto pg = CartesianPointGroup(sg, cell);
const auto rotations = RotationAsu(UniformRotations(6.0), pg);
const auto rf = RotationFunction(ft, refl, cell, sg, rotations, 4);
size_t best = 0;
for (size_t i = 1; i < rf.size(); i++)
if (rf[i] > rf[best])
best = i;
CHECK(RotationDistanceDeg(rotations[best], truth, pg) < 6.0);
// At the true orientation the translation function peaks at the true position, up to the
// origins P 21 21 21 allows (a half in each coordinate), and stands far out of its own noise.
const TranslationPeak peak = TranslationFunction(ft, MakeTranslationSetup(refl, cell, sg), truth);
CHECK(peak.z > 10.0);
for (double d : {peak.t.x - t.x, peak.t.y - t.y, peak.t.z - t.z}) {
const double half = 2 * d - std::round(2 * d);
CHECK(std::fabs(half) < 0.06);
}
}
// Two copies in the asymmetric unit: with the first one known, the translation function of the second
// at its true orientation peaks at its true position - not merely at one of the group's origins, which
// only the cross term with the known copy tells apart.
TEST_CASE("MolecularReplacement_SecondCopyBesideKnownFirst", "[MolecularReplacement]") {
const SearchModel model = synthetic_model();
const gemmi::UnitCell cell(52, 60, 70, 90, 90, 90);
const gemmi::SpaceGroup &sg = gemmi::get_spacegroup_by_name("P 21 21 21");
const gemmi::Mat33 r1 = axis_angle({1, 2, 3}, 50), r2 = axis_angle({-2, 1, 1}, 110);
const gemmi::Fractional t1(0.17, 0.31, 0.09), t2(0.41, 0.12, 0.33);
const gemmi::Structure crystal = AssembleCopies({PlaceSearchModel(model, r1, t1, cell, sg),
PlaceSearchModel(model, r2, t2, cell, sg)});
const auto merged = observed(crystal);
const SearchReflections refl = MakeSearchReflections(merged, cell, sg, 4.0, 12.0);
const MolecularTransform ft(model, 4.0, 4);
const TranslationSetup setup = MakeTranslationSetup(refl, cell, sg, true);
const auto known = KnownStructureFactors(ft, setup, cell, {r1}, {t1});
const TranslationPeak peak = TranslationFunction(ft, setup, r2, &known);
CHECK(peak.z > 10.0);
for (double d : {peak.t.x - t2.x, peak.t.y - t2.y, peak.t.z - t2.z})
CHECK(std::fabs(d - std::round(d)) < 0.04);
// Two copies of the same body in one cell do not clash where they are placed apart.
CHECK(ClashFraction(crystal, 2) < 0.05);
CHECK(ClashFraction(AssembleCopies({PlaceSearchModel(model, r1, t1, cell, sg),
PlaceSearchModel(model, r2, t1, cell, sg)}), 2) > 0.5);
}
// The likelihood of the true placement stands out over the same orientation elsewhere, and the gain is zero
// where sigma_A is.
TEST_CASE("MolecularReplacement_LikelihoodPlacement", "[MolecularReplacement]") {
const SearchModel model = synthetic_model();
const gemmi::UnitCell cell(42, 50, 58, 90, 90, 90);
const gemmi::SpaceGroup &sg = gemmi::get_spacegroup_by_name("P 21 21 21");
const gemmi::Mat33 truth = axis_angle({1, 2, 3}, 50);
const gemmi::Fractional t(0.17, 0.31, 0.09);
const auto merged = observed(PlaceSearchModel(model, truth, t, cell, sg));
const LikelihoodSetup setup = MakeLikelihoodSetup(MakeSearchReflections(merged, cell, sg, 3.5, 12.0), cell, sg);
REQUIRE(setup.Terms() > 500);
const std::vector<std::complex<double>> none(setup.Terms(), 0.0);
const auto g = CopyFactors(model, setup, cell, truth, 3.5, 4);
const LikelihoodPeak peak = LikelihoodTranslationZ(setup, none, 0.0, g, t, 0.3, 4);
CHECK(peak.llg > 100.0);
CHECK(peak.z > 8.0);
CHECK(peak.scale > 0.8);
const double wrong = LikelihoodGain(setup, none, 0.0, g, gemmi::Fractional(0.4, 0.05, 0.3), 0.3);
CHECK(wrong < peak.llg / 4);
std::vector<std::complex<double>> f = none;
AddCopy(setup, g, t, f);
CHECK(LogLikelihoodGain(setup, f, 0.3, 0.0) == Catch::Approx(0.0).margin(1e-9));
}
TEST_CASE("MolecularReplacement_ModelKind", "[MolecularReplacement]") {
// Three alanines along x, written as PDB with a CRYST1 line and the B column given per atom.
const auto write = [](const std::string &path, const char *cryst1, const float b[3], bool water, bool altloc) {
std::ofstream out(path);
out << cryst1 << "\n";
int serial = 1;
for (int r = 0; r < 3; r++)
for (const char *name : {" N ", " CA ", " C ", " O "}) {
char line[128];
const char alt = altloc && r == 1 ? 'A' : ' ';
std::snprintf(line, sizeof line, "ATOM %5d %4s%cALA A%4d %8.3f%8.3f%8.3f%6.2f%6.2f %c",
serial++, name, alt, r + 1, 3.8 * r + (name[1] == 'C' && name[2] == ' ' ? 1.5 : 0.0),
name[1] == 'O' ? 1.2 : 0.0, 0.0, 1.0, b[r], name[1]);
out << line << "\n";
if (alt == 'A') {
std::snprintf(line, sizeof line, "ATOM %5d %4sBALA A%4d %8.3f%8.3f%8.3f%6.2f%6.2f %c",
serial++, name, r + 1, 3.8 * r + 0.3, 0.3, 0.0, 0.5, b[r], name[1]);
out << line << "\n";
}
}
if (water)
out << "HETATM 100 O HOH A 101 10.000 10.000 10.000 1.00 30.00 O\n";
out << "END\n";
};
const float plddt[3] = {90, 85, 95};
write("MolecularReplacement_ModelKind_af.pdb", "CRYST1 1.000 1.000 1.000 90.00 90.00 90.00 P 1 1",
plddt, false, false);
const SearchModel af = PrepareSearchModel("MolecularReplacement_ModelKind_af.pdb");
CHECK(af.failure_reason.empty());
CHECK(af.predicted);
CHECK(af.residues_kept == 3);
// In a cell, with refined B-factors (one above 100), a water and an alternative conformer.
const float refined[3] = {25, 112, 40};
write("MolecularReplacement_ModelKind_xtal.pdb", "CRYST1 50.000 60.000 70.000 90.00 90.00 90.00 P 21 21 21 4",
refined, true, true);
const SearchModel x = PrepareSearchModel("MolecularReplacement_ModelKind_xtal.pdb");
CHECK(x.failure_reason.empty());
CHECK(!x.predicted);
CHECK(x.residues_kept == 3);
size_t atoms = 0;
for (const gemmi::Chain &ch : x.st.models[0].chains)
for (const gemmi::Residue &r : ch.residues)
atoms += r.atoms.size();
CHECK(atoms == 12); // no water, one conformer
CHECK(x.error_A == Catch::Approx(0.67).margin(0.01));
std::remove("MolecularReplacement_ModelKind_af.pdb");
std::remove("MolecularReplacement_ModelKind_xtal.pdb");
}
TEST_CASE("MolecularReplacement_PaeDomains", "[MolecularReplacement]") {
CHECK(PaePathFor("/x/AF-P12345-F1-model_v6.cif") == "/x/AF-P12345-F1-predicted_aligned_error_v6.json");
CHECK(PaePathFor("AF-P12345-F1-model_v4.pdb.gz") == "AF-P12345-F1-predicted_aligned_error_v4.json");
CHECK(PaePathFor("/x/model.cif").empty());
// A prediction of 120 residues: two confident blocks, 1-50 and 61-120, placed relative to each other
// with no confidence, and a loop 51-60 the trim removed.
SearchModel m;
gemmi::Model model(1);
gemmi::Chain chain("A");
for (int i = 0; i < 120; i++) {
if (i >= 50 && i < 60)
continue;
gemmi::Residue r;
r.name = "ALA";
r.seqid = gemmi::SeqId(i + 1, ' ');
gemmi::Atom a;
a.name = "CA";
a.element = gemmi::El::C;
a.pos = gemmi::Position(3.8 * i, i < 50 ? 0.0 : 20.0, 0.0);
a.b_iso = 10.0f;
a.occ = 1.0f;
r.atoms.push_back(a);
chain.residues.push_back(r);
m.residue_index.push_back(i);
}
model.chains.push_back(chain);
m.st.models.push_back(model);
m.residues_read = 120;
m.residues_kept = 110;
const std::string path = "MolecularReplacement_PaeDomains.json";
{
std::ofstream out(path);
out << "[{\"predicted_aligned_error\":[";
for (int i = 0; i < 120; i++) {
out << (i ? "," : "") << "[";
for (int j = 0; j < 120; j++)
out << (j ? "," : "") << ((i < 55) == (j < 55) ? 2 : 25);
out << "]";
}
out << "],\"max_predicted_aligned_error\":31.75}]";
}
const auto domains = PaeDomains(path, m);
REQUIRE(domains.size() == 2);
CHECK(domains[0].size() == 60);
CHECK(domains[0].front() == 60);
CHECK(domains[1].size() == 50);
const SearchModel d = DomainModel(m, domains[1]);
CHECK(d.residues_kept == 50);
CHECK(d.description == "PAE domain of 50 residues (1-50)");
std::remove(path.c_str());
}
// A placement of a group carried into a subgroup's merge: in P 21 21 21 read as P 1 21 1 on the same cell each
// copy becomes two, the second its image under a two-fold the subgroup does not have; in C 2 2 21 read as
// P 1 21 1 on the primitive monoclinic cell half the volume holds the same two.
TEST_CASE("MolecularReplacement_ExpandIntoSubgroup", "[MolecularReplacement]") {
const SearchModel model = synthetic_model();
{
const gemmi::UnitCell cell(42, 50, 58, 90, 90, 90);
const gemmi::SpaceGroup &g = gemmi::get_spacegroup_by_name("P 21 21 21");
const gemmi::SpaceGroup &h = gemmi::get_spacegroup_by_name("P 1 21 1");
const auto setting = SubgroupBasis(cell, g, cell, h);
REQUIRE(setting);
const gemmi::Structure placed = PlaceSearchModel(model, axis_angle({1, 2, 3}, 50), gemmi::Fractional(0.17, 0.31, 0.09), cell, g);
int n = 0;
const gemmi::Structure expanded = ExpandIntoSubgroup(placed, 1, g, *setting, cell, h, &n);
CHECK(n == 2);
// The same crystal: the copies and their P 1 21 1 mates are the P 21 21 21 crystal, which packs.
CHECK(ClashFraction(expanded, 2) < 0.05);
}
{
const gemmi::UnitCell g_cell(56, 158, 144, 90, 90, 90);
const gemmi::SpaceGroup &g = gemmi::get_spacegroup_by_name("C 2 2 21");
const double half = std::sqrt(56.0 * 56.0 + 158.0 * 158.0) / 2;
const double beta = 180.0 - std::acos(28.0 / half) * 180.0 / M_PI;
const gemmi::UnitCell h_cell(half, 144, 56, 90, beta, 90);
const gemmi::SpaceGroup &h = gemmi::get_spacegroup_by_name("P 1 21 1");
const auto setting = SubgroupBasis(g_cell, g, h_cell, h);
REQUIRE(setting);
CHECK(std::fabs(setting->basis.determinant() - 0.5) < 1e-9);
const gemmi::Structure placed = PlaceSearchModel(model, axis_angle({1, 2, 3}, 50), gemmi::Fractional(0.17, 0.31, 0.09), g_cell, g);
int n = 0;
const gemmi::Structure expanded = ExpandIntoSubgroup(placed, 1, g, *setting, h_cell, h, &n);
CHECK(n == 2);
CHECK(ClashFraction(expanded, 2) < 0.05);
}
}
TEST_CASE("MolecularReplacement_MatthewsProbabilities", "[MolecularReplacement]") {
// Vm 2.5 A^3/Da for one copy: one copy is by far the most probable, four impossible (Vm 0.6).
const auto p = MatthewsProbabilities(2.5 * 20000, 20000);
REQUIRE(p.size() == 1);
CHECK(p[0] == Catch::Approx(1.0));
// Vm 9 for one copy: three or four copies (Vm 3, 2.25) are the likely ones, one copy is not.
const auto q = MatthewsProbabilities(9.0 * 20000, 20000);
REQUIRE(q.size() == 6);
CHECK(q[0] < 0.01);
CHECK(std::max_element(q.begin(), q.end()) - q.begin() == 3);
}
TEST_CASE("MolecularReplacement_TranslationalNcs", "[MolecularReplacement]") {
const SearchModel model = synthetic_model();
const gemmi::UnitCell cell(52, 60, 90, 90, 90, 90);
const gemmi::SpaceGroup &sg = gemmi::get_spacegroup_by_name("P 21 21 21");
const gemmi::Mat33 r = axis_angle({1, 2, 3}, 50);
const gemmi::Fractional t(0.17, 0.31, 0.09), v(0.0, 0.0, 0.5);
const auto one = observed(PlaceSearchModel(model, r, t, cell, sg));
CHECK_FALSE(DetectTranslationalNcs(one, cell, sg).present);
const auto two = observed(AssembleCopies({PlaceSearchModel(model, r, t, cell, sg),
PlaceSearchModel(model, r, gemmi::Fractional(t.x, t.y, t.z + v.z), cell, sg)}));
const TranslationalNcs tncs = DetectTranslationalNcs(two, cell, sg);
REQUIRE(tncs.present);
CHECK(std::fabs(tncs.vector.x - std::round(tncs.vector.x)) < 0.03);
CHECK(std::fabs(tncs.vector.y - std::round(tncs.vector.y)) < 0.03);
CHECK(std::fabs(tncs.vector.z - 0.5) < 0.03);
}
TEST_CASE("MolecularReplacement_TncsRelatesGroups", "[MolecularReplacement]") {
const auto &p3121 = gemmi::get_spacegroup_by_name("P 31 2 1"), &p3221 = gemmi::get_spacegroup_by_name("P 32 2 1");
// A translation of c/3 turns a 3(1) axis into a 3(2) one, wherever it lies in the plane.
CHECK(TncsRelatesGroups(p3121, p3221, gemmi::Fractional(0.3, 0.1, 1.0 / 3)));
CHECK_FALSE(TncsRelatesGroups(p3121, p3221, gemmi::Fractional(0.3, 0.1, 0.1)));
// A translation of a/2 turns 2(1) along a into 2, and nothing else.
const auto &p212121 = gemmi::get_spacegroup_by_name("P 21 21 21");
CHECK(TncsRelatesGroups(gemmi::get_spacegroup_by_name("P 2 21 21"), p212121, gemmi::Fractional(0.5, 0, 0)));
CHECK_FALSE(TncsRelatesGroups(gemmi::get_spacegroup_by_name("P 21 2 2"), p212121, gemmi::Fractional(0.5, 0, 0)));
}
// A copy refined beside another one held fixed goes back where it belongs, on the CPU and on the GPU alike.
TEST_CASE("MolecularReplacement_RigidBodyBesideFixedCopy", "[MolecularReplacement]") {
const SearchModel model = synthetic_model();
const gemmi::UnitCell cell(52, 60, 70, 90, 90, 90);
const gemmi::SpaceGroup &sg = gemmi::get_spacegroup_by_name("P 21 21 21");
const gemmi::Mat33 r1 = axis_angle({1, 2, 3}, 50), r2 = axis_angle({-2, 1, 1}, 110);
const gemmi::Fractional t1(0.17, 0.31, 0.09), t2(0.41, 0.12, 0.33);
const gemmi::Structure first = PlaceSearchModel(model, r1, t1, cell, sg);
const gemmi::Structure truth = PlaceSearchModel(model, r2, t2, cell, sg);
const auto merged = observed(AssembleCopies({first, truth}));
gemmi::AsuData<gemmi::ValueSigma<float>> fobs;
fobs.unit_cell_ = cell;
fobs.spacegroup_ = &sg;
for (const MergedReflection &m : merged)
fobs.v.push_back({{{m.h, m.k, m.l}}, {m.F, 1.0f}});
fobs.ensure_asu();
fobs.ensure_sorted();
// 3 deg and 0.5 A out.
const gemmi::Structure start = PlaceSearchModel(model, axis_angle({0, 0, 1}, 3).multiply(r2),
gemmi::Fractional(t2.x + 0.5 / 52, t2.y, t2.z), cell, sg);
const auto worst = [&](const gemmi::Structure &st) {
const auto a = ModelPositions(st.models[0]), b = ModelPositions(truth.models[0]);
double w = 0;
for (size_t i = 0; i < a.size(); i++)
w = std::max(w, a[i].dist(b[i]));
return w;
};
Logger logger("MolecularReplacement_RigidBodyBesideFixedCopy");
gemmi::Structure cpu = start;
RefineRigidBody(cpu.models[0], cell, sg, fobs, 3.0, logger, 4, nullptr, &first.models[0]);
CHECK(worst(start) > 1.0);
CHECK(worst(cpu) < 0.1);
#ifdef JFJOCH_USE_CUDA
if (get_gpu_count() > 0) {
gemmi::Structure gpu = start;
auto pool = RigidBodyGPUPool::Create(gpu.models[0], cell, sg, 3.0, fobs.v.size(), 1, logger);
REQUIRE(pool);
RefineRigidBody(gpu.models[0], cell, sg, fobs, 3.0, logger, 4, pool.get(), &first.models[0]);
CHECK(worst(gpu) < 0.1);
}
#endif
}
#ifdef JFJOCH_USE_CUDA
TEST_CASE("MolecularReplacement_GPUMatchesCPU", "[MolecularReplacement]") {
if (get_gpu_count() == 0)
SKIP("no GPU");
const SearchModel model = synthetic_model();
const gemmi::UnitCell cell(42, 50, 58, 90, 90, 90);
const gemmi::SpaceGroup &sg = gemmi::get_spacegroup_by_name("P 21 21 21");
const gemmi::Mat33 truth = axis_angle({1, 2, 3}, 50);
const gemmi::Fractional t(0.17, 0.31, 0.09);
const auto merged = observed(PlaceSearchModel(model, truth, t, cell, sg));
const SearchReflections refl = MakeSearchReflections(merged, cell, sg, 4.0, 12.0);
const MolecularTransform ft(model, 4.0, 4);
MolecularReplacementGPU gpu(ft);
const auto rotations = RotationAsu(UniformRotations(15.0), CartesianPointGroup(sg, cell));
const auto rf_cpu = RotationFunction(ft, refl, cell, sg, rotations, 4);
const auto rf_gpu = gpu.RotationFunction(refl, cell, sg, rotations);
REQUIRE(rf_gpu.size() == rf_cpu.size());
for (size_t i = 0; i < rf_cpu.size(); i++)
CHECK(std::fabs(rf_gpu[i] - rf_cpu[i]) < 1e-4);
const TranslationSetup setup = MakeTranslationSetup(refl, cell, sg);
std::vector<gemmi::Mat33> orientations{truth, rotations[3], rotations[17]};
const auto tf_gpu = gpu.TranslationFunction(setup, orientations);
for (size_t i = 0; i < orientations.size(); i++) {
const TranslationPeak cpu = TranslationFunction(ft, setup, orientations[i]);
CHECK(std::fabs(tf_gpu[i].z - cpu.z) < 1e-3);
// The solution's peak is the same up to the origins P 21 21 21 allows, which tie exactly; noise peaks
// can tie between grid points.
if (i == 0)
for (double d : {tf_gpu[i].t.x - cpu.t.x, tf_gpu[i].t.y - cpu.t.y, tf_gpu[i].t.z - cpu.t.z})
CHECK(std::fabs(2 * d - std::round(2 * d)) < 1e-6);
}
// The molecular transform's FFT.
gemmi::DensityCalculator<gemmi::IT92<float>, float> dc;
dc.d_min = 4.0;
dc.rate = 1.5;
gemmi::Structure st = PlaceSearchModel(model, truth, t, cell, gemmi::get_spacegroup_p1());
dc.set_grid_cell_and_spacegroup(st);
dc.put_model_density_on_grid(st.models[0]);
REQUIRE(MapToFPhiGPUFits(dc.grid));
const auto f_cpu = MapToFPhi(dc.grid), f_gpu = MapToFPhiGPU(dc.grid);
REQUIRE(f_gpu.data.size() == f_cpu.data.size());
double worst = 0, largest = 0;
for (size_t i = 0; i < f_cpu.data.size(); i++) {
worst = std::max(worst, static_cast<double>(std::abs(f_gpu.data[i] - f_cpu.data[i])));
largest = std::max(largest, static_cast<double>(std::abs(f_cpu.data[i])));
}
CHECK(worst < 1e-4 * largest);
// Beside a known copy.
const TranslationSetup setup2 = MakeTranslationSetup(refl, cell, sg, true);
const auto known = KnownStructureFactors(ft, setup2, cell, {rotations[5]}, {gemmi::Fractional(0.3, 0.1, 0.4)});
const auto tf2_gpu = gpu.TranslationFunction(setup2, orientations, &known);
for (size_t i = 0; i < orientations.size(); i++) {
const TranslationPeak cpu = TranslationFunction(ft, setup2, orientations[i], &known);
CHECK(std::fabs(tf2_gpu[i].z - cpu.z) < 1e-3);
}
}
#endif