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v1.0.0-rc.183 (#94)
* jfjoch_broker (experimental): Serial data are merged live, with intermediate results during the collection.
* Rugnux: More robust processing of serial data, including CCD detectors.
* Rugnux: Parts of a rotation sweep that spoil the merge are removed automatically.
* Rugnux: Clearer maps, and anomalous peaks not explained by the model are reported.
* Rugnux: SHELX files work with SHELXL; XFEL pulse IDs are kept in `_process.h5`.
* Web frontend: Spot-finding settings change only when the user changes them.
* Rugnux: Faster processing.

Reviewed-on: #94
Co-authored-by: Filip Leonarski <filip.leonarski@psi.ch>
2026-11-06 03:34:07 +01:00

1052 lines
54 KiB
C++

// SPDX-FileCopyrightText: 2025 Filip Leonarski, Paul Scherrer Institute <filip.leonarski@psi.ch>
// SPDX-License-Identifier: GPL-3.0-only
#include "StillsPartialityRefine.h"
#include <algorithm>
#include <array>
#include <atomic>
#include <cmath>
#include <future>
#include <limits>
#include <thread>
#include <vector>
#include <Eigen/Dense>
#include <ceres/rotation.h>
#include "Merge.h"
#include "../../common/Logger.h"
#include "../../common/ThreadAffinity.h"
#include "../../common/ParallelFor.h"
namespace {
constexpr size_t MIN_FIT_REFLECTIONS = 20;
constexpr double kRadToDeg = 180.0 / 3.14159265358979323846;
// Model error of the per-crystal scale fit, as a fraction of the predicted intensity - ScaleOnTheFly's.
constexpr double SCALE_MODEL_ERROR = 0.3;
// The width scales BalanceRunWidth searches: from 1/BALANCE_RANGE to BALANCE_RANGE times the table.
constexpr double BALANCE_RANGE = 3.0;
// The smallest priors on a crystal's radial scale and log width scale (RunPrior).
constexpr double MIN_PRIOR_ETA = 1e-5;
constexpr double MIN_PRIOR_LN_WIDTH = 0.01;
double SafeInv(double x, double fallback) {
if (!std::isfinite(x) || x == 0.0)
return fallback;
return 1.0 / x;
}
// One accepted reflection reduced to the physical partiality fit: the base reciprocal vector q (crystal
// frame at the stored per-image orientation), the reference full intensity, the measured intensity, the
// reciprocal of the prescaling correction (the factor that turns a true intensity back into counts),
// the measured variance and its background part, and the weight the tilt is refined with.
// dist_ewald / partiality are recomputed from q under the refined tilt.
struct FitObs {
double qx, qy, qz;
double Iref;
double Iobs;
double inv_corr; // 1 / (prescaling_corr * qe_corr * flight_corr)
double sigma2;
double var_bkg;
double weight; // 1 / sqrt(variance at the current model), set with each G
};
// The variance of an observation at the model m: background, the counting noise of m and the model error.
double ModelVariance(const FitObs &o, double m) {
return o.var_bkg + std::max(0.0, m) + SCALE_MODEL_ERROR * SCALE_MODEL_ERROR * m * m;
}
double VecLen(double x, double y, double z) { return std::sqrt(x * x + y * y + z * z); }
// The rocking width sigma^2 at a reflection of resolution d* (and |q_z|, for the bandwidth term): the
// run's table where there is one - linear in d* between its shells, held beyond the outermost - else
// the three-term formula.
struct Width {
double gamma0, gamma_e, bw;
const std::vector<double> *table_dstar = nullptr, *table_s = nullptr;
double Sigma2(double dstar, double qz) const {
if (table_dstar && !table_dstar->empty()) {
const auto &x = *table_dstar;
const auto &y = *table_s;
double s = y.front();
if (dstar >= x.back())
s = y.back();
else if (dstar > x.front()) {
const size_t i = std::upper_bound(x.begin(), x.end(), dstar) - x.begin();
s = y[i - 1] + (dstar - x[i - 1]) / (x[i] - x[i - 1]) * (y[i] - y[i - 1]);
}
return s * s;
}
const double sig_ang = gamma_e * dstar;
const double sbw = bw * std::fabs(qz);
return gamma0 * gamma0 + sig_ang * sig_ang + sbw * sbw;
}
};
// The prediction window cuts the rocking curve. Reflections fill a window of half-width W evenly, so
// their plain moment of de is u = W^2 / 3, and the intensity-weighted moment m of a Gaussian of width
// s cut at +-W is u * g(a), a = W / s, with g(a) = 3/a^2 (1 - 2 a phi(a) / erf(a / sqrt 2)): 1 for a
// curve much wider than the window, s^2 / u for a much narrower one. Solves g(a) = m / u for s^2 by
// bisection (g falls with a). A curve wider than the window cannot be measured through it: empty.
std::optional<double> UntruncatedVariance(double m, double u) {
auto g = [](double a) {
const double phi = std::exp(-0.5 * a * a) / std::sqrt(2.0 * 3.14159265358979323846);
return 3.0 / (a * a) * (1.0 - 2.0 * a * phi / std::erf(a / std::sqrt(2.0)));
};
const double t = m / u;
double lo = 1.0, hi = 50.0;
if (!(t < g(lo)))
return std::nullopt;
for (int i = 0; i < 60; ++i) {
const double mid = 0.5 * (lo + hi);
(g(mid) > t ? lo : hi) = mid;
}
const double a = 0.5 * (lo + hi);
return 3.0 * u / (a * a);
}
// Robust per-crystal scale G (linear in G given the model coefficients), the objective of
// ScaleOnTheFly::SolveScaleIRLS: minimise sum Cauchy_k( (G*coeff - Iobs) / sqrt(var(G*coeff)) ) over G >= 0,
// the variances re-evaluated at each step's G.
double SolveScaleIRLS(const std::vector<FitObs> &obs, const std::vector<double> &coeff, double robust_k) {
double num = 0.0, den = 0.0;
for (size_t i = 0; i < obs.size(); ++i) {
num += coeff[i] * obs[i].Iobs / obs[i].sigma2;
den += coeff[i] * coeff[i] / obs[i].sigma2;
}
if (!(den > 0.0) || !std::isfinite(num / den))
return 1.0;
double G = std::max(0.0, num / den);
const double k2 = robust_k * robust_k;
for (int iter = 0; iter < 30; ++iter) {
num = den = 0.0;
for (size_t i = 0; i < obs.size(); ++i) {
const double res = G * coeff[i] - obs[i].Iobs;
const double w = 1.0 / (ModelVariance(obs[i], G * coeff[i]) + res * res / k2);
num += w * coeff[i] * obs[i].Iobs;
den += w * coeff[i] * coeff[i];
}
if (!(den > 0.0) || !std::isfinite(num / den))
break;
const double G_prev = G;
G = std::max(0.0, num / den);
if (std::abs(G - G_prev) <= 1e-7 * std::max(G, 1.0))
break;
}
return G;
}
// The rotation by the angle-axis vector (psi_x, psi_y, 0) as a matrix (Rodrigues), so that one tilt
// is applied to all the reflections of a crystal by a matrix product each.
std::array<double, 9> TiltMatrix(double psi_x, double psi_y) {
const double theta = std::sqrt(psi_x * psi_x + psi_y * psi_y);
if (theta < 1e-15)
return {1.0, 0.0, 0.0, 0.0, 1.0, 0.0, 0.0, 0.0, 1.0};
const double kx = psi_x / theta, ky = psi_y / theta;
const double c = std::cos(theta), s = std::sin(theta), t = 1.0 - c;
return {c + t * kx * kx, t * kx * ky, s * ky,
t * kx * ky, c + t * ky * ky, -s * kx,
-s * ky, s * kx, c};
}
// A crystal's model of its partialities: the orientation tilt (psi_x, psi_y) about the two axes
// perpendicular to the beam, a radial scale eta of its reciprocal lattice (q -> (1 + eta) q: a
// wavelength or a cell a little off for this crystal - on an XFEL the photon energy of its shot) and a
// scale exp(ln_width) of the run's rocking width (a crystal's own mosaicity or domain size).
// Per-crystal mosaicity and lattice scale in post-refinement, following Uervirojnangkoorn et al. (2015)
// eLife 4, e05421 and Sauter et al. (2014) Acta Cryst. D70, 3299-3309.
struct CrystalModel {
double psi_x = 0.0, psi_y = 0.0, eta = 0.0, ln_width = 0.0;
double width2 = 1.0; // exp(2 ln_width), the factor on the run's sigma^2
};
CrystalModel MakeCrystalModel(double psi_x, double psi_y, double eta, double ln_width) {
return {psi_x, psi_y, eta, ln_width, std::exp(2.0 * ln_width)};
}
// The partiality of a reflection whose base reciprocal vector is q under a crystal model. Mirrors
// BraggPrediction: dist_ewald = |S| - 1/lambda with S = q' + S0, q' = (1 + eta) R(psi) q, and
// p = exp(-dist_ewald^2 / 2 sigma^2), sigma = exp(ln_width) sigma_run(d*).
struct PartialityModel {
double s0x, s0y, s0z, inv_lambda;
Width width;
double At(const std::array<double, 9> &R, const CrystalModel &m, double qx0, double qy0, double qz0) const {
const double f = 1.0 + m.eta;
const double qx = f * (R[0] * qx0 + R[1] * qy0 + R[2] * qz0);
const double qy = f * (R[3] * qx0 + R[4] * qy0 + R[5] * qz0);
const double qz = f * (R[6] * qx0 + R[7] * qy0 + R[8] * qz0);
const double de = VecLen(qx + s0x, qy + s0y, qz + s0z) - inv_lambda;
const double sig2 = width.Sigma2(VecLen(qx, qy, qz), qz) * m.width2;
if (!(sig2 > 0.0))
return 1.0;
return std::exp(-0.5 * de * de / sig2);
}
double P(const std::array<double, 9> &R, const CrystalModel &m, const FitObs &o) const {
return At(R, m, o.qx, o.qy, o.qz);
}
};
// Refine the crystal model holding the scale G fixed: minimise
// sum_i rho(r_i^2) / 2 + sum_k (x_k / sigma_k)^2 / 2, r_i = weight_i (G p_i(x) Iref_i / corr_i - Iobs_i),
// over x = (psi_x, psi_y, eta, ln_width), with the Cauchy rho(s) = k^2 log(1 + s / k^2) - the intensity-
// space objective of ScaleOnTheFly - and Gaussian priors about the run (x = 0), proper MAP terms since
// r_i is already in sigma units. Levenberg-Marquardt on the normal equations reweighted by rho', the
// Jacobian by forward differences in the tilt and the radial scale (the model at x is the residual's
// already) and exact in the width, dp / d ln_width = -2 p ln p, every trial held inside the bounds. Returns false when the cost
// cannot be evaluated, leaving the model as it came in.
bool RefineCrystal(const std::vector<FitObs> &obs, const PartialityModel &model, double G, double robust_k,
const std::array<double, 4> &inv_sigma_prior, const std::array<double, 4> &bound,
CrystalModel &crystal, std::array<double, 4> &variance) {
constexpr int MAX_ITERATIONS = 25;
constexpr std::array<double, 3> STEP = {1e-7, 1e-7, 1e-7}; // for the forward differences
const double k2 = robust_k * robust_k;
auto as_model = [](const Eigen::Vector4d &x) { return MakeCrystalModel(x(0), x(1), x(2), x(3)); };
auto cost = [&](const Eigen::Vector4d &x) {
const auto R = TiltMatrix(x(0), x(1));
const CrystalModel m = as_model(x);
double c = 0.0;
for (int k = 0; k < 4; ++k)
c += 0.5 * inv_sigma_prior[k] * inv_sigma_prior[k] * x(k) * x(k);
for (const auto &o: obs) {
const double r = o.weight * (G * model.P(R, m, o) * o.inv_corr * o.Iref - o.Iobs);
c += 0.5 * k2 * std::log1p(r * r / k2);
}
return c;
};
Eigen::Vector4d x(crystal.psi_x, crystal.psi_y, crystal.eta, crystal.ln_width);
double current = cost(x);
if (!std::isfinite(current))
return false;
double lambda = 1e-4;
Eigen::Matrix4d data_A = Eigen::Matrix4d::Identity(); // the normal matrix of the data alone
for (int iter = 0; iter < MAX_ITERATIONS; ++iter) {
Eigen::Matrix4d A = Eigen::Matrix4d::Zero();
Eigen::Vector4d b = Eigen::Vector4d::Zero();
for (int k = 0; k < 4; ++k) {
A(k, k) = inv_sigma_prior[k] * inv_sigma_prior[k];
b(k) = A(k, k) * x(k);
}
// The model at x and at x + one step in each of the tilts and the radial scale.
std::array<std::array<double, 9>, 4> R;
std::array<CrystalModel, 4> m;
for (int j = 0; j < 4; ++j) {
Eigen::Vector4d xj = x;
if (j > 0)
xj(j - 1) += STEP[j - 1];
R[j] = TiltMatrix(xj(0), xj(1));
m[j] = as_model(xj);
}
for (const auto &o: obs) {
const double a = o.weight * G * o.inv_corr * o.Iref;
const double p0 = model.P(R[0], m[0], o);
const double r = a * p0 - o.weight * o.Iobs;
Eigen::Vector4d J;
for (int k = 0; k < 3; ++k)
J(k) = a * (model.P(R[k + 1], m[k + 1], o) - p0) / STEP[k];
J(3) = p0 > 0.0 ? -2.0 * a * p0 * std::log(p0) : 0.0;
const double w = 1.0 / (1.0 + r * r / k2); // rho'
A += w * J * J.transpose();
b += w * r * J;
}
data_A = A;
for (int k = 0; k < 4; ++k)
data_A(k, k) -= inv_sigma_prior[k] * inv_sigma_prior[k];
bool accepted = false;
Eigen::Vector4d trial = x;
double trial_cost = current;
while (lambda < 1e10) {
Eigen::Matrix4d M = A;
M.diagonal() *= 1.0 + lambda;
const Eigen::Vector4d dx = M.ldlt().solve(b);
if (!dx.allFinite())
break;
for (int k = 0; k < 4; ++k)
trial(k) = std::clamp(x(k) - dx(k), -bound[k], bound[k]);
trial_cost = cost(trial);
if (std::isfinite(trial_cost) && trial_cost < current) {
accepted = true;
lambda = std::max(lambda / 10.0, 1e-12);
break;
}
lambda *= 10.0;
}
if (!accepted)
break;
const double decrease = current - trial_cost;
const double step = (trial - x).norm();
x = trial;
current = trial_cost;
if (decrease <= 1e-6 * current || step <= 1e-10)
break;
}
crystal = as_model(x);
const Eigen::Matrix4d cov = data_A.inverse();
for (int k = 0; k < 4; ++k)
variance[k] = cov(k, k);
return true;
}
}
StillsPartialityRefine::StillsPartialityRefine(const DiffractionExperiment &x)
: experiment_(x),
hkl_key_generator_(x.GetScalingSettings().GetMergeFriedel(), x.GetSpaceGroupOrP1()),
d_min_limit_(x.GetScalingSettings().GetHighResolutionLimit_A()),
d_max_limit_(x.GetScalingSettings().GetLowResolutionLimit_A()),
min_partiality_(x.GetScalingSettings().GetMinPartiality()),
bandwidth_sigma_(x.GetBandwidthFWHM().value_or(0.0f) / 2.3548f) {}
StillsPartialityRefine::CrystalFit StillsPartialityRefine::RefineOne(IntegrationOutcome &outcome,
const std::map<HKLKey, double> &reference,
const std::optional<RunWidth> &run_width,
double radial_scale, const CrystalPrior &prior) const {
if (outcome.reflections.empty())
return {};
const Coord Astar = outcome.latt.Astar();
const Coord Bstar = outcome.latt.Bstar();
const Coord Cstar = outcome.latt.Cstar();
const Coord S0 = outcome.geom.GetScatteringVector();
const double inv_lambda = 1.0 / outcome.geom.GetWavelength_A();
auto base_q = [&](const Reflection &r) {
return (Astar * static_cast<float>(r.h) + Bstar * static_cast<float>(r.k)
+ Cstar * static_cast<float>(r.l)) * static_cast<float>(radial_scale);
};
// Collect the reflections that constrain the fit (accepted, non-ice, finite, present in the reference).
std::vector<FitObs> obs;
obs.reserve(outcome.reflections.size());
// Moments of the excitation error against resolution: de^2 ~ gamma0^2 + gamma_e^2 * d*^2, fitted per
// crystal by ordinary least squares on (d*^2, de^2). Both components come out of the data.
double m_n = 0.0, m_x = 0.0, m_xx = 0.0, m_y = 0.0, m_xy = 0.0;
size_t n_de = 0;
for (const Reflection &r: outcome.reflections) {
if (r.on_ice_ring || !AcceptReflection(r, d_min_limit_, d_max_limit_))
continue;
if (!std::isfinite(r.I) || !std::isfinite(r.sigma) || r.sigma <= 0.0f)
continue;
const auto it = reference.find(hkl_key_generator_(r));
if (it == reference.end() || !std::isfinite(it->second))
continue;
const Coord q = base_q(r);
obs.push_back(FitObs{
.qx = q.x, .qy = q.y, .qz = q.z,
.Iref = it->second,
.Iobs = static_cast<double>(r.I),
.inv_corr = SafeInv(r.prescaling_corr * r.qe_corr * r.flight_corr, 1.0),
.sigma2 = static_cast<double>(r.sigma) * r.sigma,
.var_bkg = std::isfinite(r.var_bkg) && r.var_bkg > 0.0f ? r.var_bkg : static_cast<double>(r.sigma) * r.sigma,
.weight = SafeInv(r.sigma, 1.0),
});
// Excitation error at the stored orientation (psi = 0), collected as the moments of de^2 against
// d*^2, so BOTH width components are fitted rather than one being forced to zero. Forcing the
// width to be purely angular (gamma0 = 0) pins it to the high-resolution edge - it is fitted over
// a d*^2-dense population - and it then collapses at low d*, giving p ~ 0 for reflections that
// were plainly recorded, which inflated the merged low-resolution intensity scale ~3.6x.
const double dstar = VecLen(q.x, q.y, q.z);
const double de0 = VecLen(q.x + S0.x, q.y + S0.y, q.z + S0.z) - inv_lambda;
if (dstar > 1e-9) {
const double x = dstar * dstar, y = de0 * de0;
m_n += 1.0;
m_x += x;
m_xx += x * x;
m_y += y;
m_xy += x * y;
++n_de;
}
}
if (obs.size() < MIN_FIT_REFLECTIONS || n_de == 0)
return {};
// Without the run's measured width (too few reflections in the run to measure it), the width comes
// from this crystal's own reflections. Solve the 2x2 normal equations for de^2 = A + B d*^2. A degenerate spread in d* (all reflections in
// one shell) leaves B undetermined, so fall back to the pure angular width there; a negative fitted
// component is unphysical and is clamped to zero, which reduces to the previous model.
//
// Measured outcome, worth knowing before touching this: the fit does NOT split the width between the
// two terms - it returns gamma0 ~ 4e-4 1/A and gamma_e ~ 0 (their cross-over sits at d = 0.3 A, far
// outside any measured range), i.e. a width constant in the LINEAR Ewald distance. That is
// structural, not a fluke: prediction accepts reflections on a fixed linear |dist_ewald| cutoff, so
// the accepted population's de^2 is flat in d*^2 by construction and the slope is genuinely ~0. The
// truncated population cannot constrain an angular term, and its width is the window's, not the
// crystal's - which is why the run's measured width is used wherever there is one.
const double det = m_n * m_xx - m_x * m_x;
double A = 0.0, B = 0.0;
if (std::fabs(det) > 1e-30) {
A = (m_xx * m_y - m_x * m_xy) / det;
B = (m_n * m_xy - m_x * m_y) / det;
} else {
B = m_x > 0.0 ? m_y / m_x : 0.0;
}
double gamma0 = std::sqrt(std::max(0.0, A));
const double gamma_e_fit = std::max(std::sqrt(std::max(0.0, B)), 1e-9);
double gamma_e = settings_.gamma_e > 0.0 ? settings_.gamma_e : gamma_e_fit;
double bw = bandwidth_sigma_;
if (run_width) {
gamma0 = run_width->gamma0;
gamma_e = std::max(run_width->gamma_e, 1e-9);
bw = run_width->bandwidth_sigma;
}
const Width width{.gamma0 = gamma0, .gamma_e = gamma_e, .bw = bw,
.table_dstar = run_width ? &run_width->table_dstar : nullptr,
.table_s = run_width ? &run_width->table_s : nullptr};
CrystalModel crystal;
double G = 1.0;
const PartialityModel model{.s0x = S0.x, .s0y = S0.y, .s0z = S0.z, .inv_lambda = inv_lambda, .width = width};
const bool refine_crystal = obs.size() >= settings_.min_reflections;
const int inner = refine_crystal ? settings_.inner_iterations : 1;
const std::array<double, 4> inv_sigma_prior = {kRadToDeg / settings_.prior_sigma_deg,
kRadToDeg / settings_.prior_sigma_deg,
1.0 / prior.sigma_eta, 1.0 / prior.sigma_ln_width};
std::array<double, 4> variance{NAN, NAN, NAN, NAN};
const std::array<double, 4> bound = {settings_.max_tilt_rad, settings_.max_tilt_rad,
settings_.max_eta, settings_.max_ln_width};
for (int it = 0; it < inner; ++it) {
// (1) Solve G given the current partialities, and weight the model fit by the variances at that model.
const auto R = TiltMatrix(crystal.psi_x, crystal.psi_y);
std::vector<double> coeff(obs.size());
for (size_t j = 0; j < obs.size(); ++j)
coeff[j] = model.P(R, crystal, obs[j]) * obs[j].inv_corr * obs[j].Iref;
G = SolveScaleIRLS(obs, coeff, settings_.robust_k);
if (!(G > 0.0) || !std::isfinite(G))
return {};
for (size_t j = 0; j < obs.size(); ++j)
obs[j].weight = 1.0 / std::sqrt(ModelVariance(obs[j], G * coeff[j]));
if (!refine_crystal)
break;
// (2) Refine the crystal model holding G fixed. A cost that cannot be evaluated keeps the model this
// crystal came in with and stops refining it - G alone is still a usable model.
if (!RefineCrystal(obs, model, G, settings_.robust_k, inv_sigma_prior, bound, crystal, variance))
break;
}
// Write the refined partiality + scale correction onto every reflection of the crystal (not only the
// fit subset), so the merge sees a consistent model. image_scale_corr = prescaling_corr * qe_corr * flight_corr /
// (partiality * G), the same composition ScaleOnTheFly writes.
const auto R = TiltMatrix(crystal.psi_x, crystal.psi_y);
for (auto &r: outcome.reflections) {
const Coord q = base_q(r);
const double p = model.At(R, crystal, q.x, q.y, q.z);
r.partiality = static_cast<float>(p);
const float corr = r.prescaling_corr * r.qe_corr * r.flight_corr;
const double denom = p * G;
r.image_scale_corr = (std::isfinite(corr) && std::isfinite(denom) && denom > 0.0)
? static_cast<float>(corr / denom)
: NAN;
}
outcome.image_scale_g = static_cast<float>(G);
// The corrections just changed, so the CC that ScaleOnTheFly measured no longer describes them.
// Refresh it here: it is reported per image and --min-image-cc drops images by it, so it has to be
// the CC of the data that is actually merged.
const auto [cc, cc_n] = ImageReferenceCC(outcome.reflections, reference, hkl_key_generator_,
d_min_limit_, d_max_limit_, min_partiality_);
outcome.image_scale_cc = cc;
outcome.image_scale_cc_n = cc_n;
return {.refined = refine_crystal, .tilt_deg = std::hypot(crystal.psi_x, crystal.psi_y) * kRadToDeg,
.eta = crystal.eta, .ln_width = crystal.ln_width, .var_eta = variance[2], .var_ln_width = variance[3]};
}
double StillsPartialityRefine::MeasureRadialScale(const std::vector<IntegrationOutcome> &outcomes,
const std::optional<UnitCell> &reference_cell,
double radial_scale) const {
// A scale of the reciprocal lattice - a wavelength, or a cell, a little off - leaves every spot where
// it was (positions fix only lambda d*), but moves each reflection's excitation error by
// eps lambda d*^2 / 2 for q -> (1 + eps) q, so the run's rocking curve sits off zero by an amount
// growing as d*^2. The prediction window is symmetric in de, so the intensity-weighted mean de of a
// shell is that offset, and a line through the origin in lambda d*^2 / 2 gives eps. A window that cuts
// an off-centre curve pulls the mean toward zero, so the caller iterates from the scale found.
const auto &indexing = experiment_.GetIndexingSettings();
struct Point { double x, de, w; };
std::vector<Point> pts;
double max_x = 0.0;
for (const auto &o: outcomes) {
if (!o.image_scale_g || !(*o.image_scale_g > 0.0))
continue;
if (reference_cell && !o.latt.GetUnitCell().is_close(*reference_cell, indexing.GetUnitCellDistTolerance(),
indexing.GetUnitCellAngleTolerance_deg()))
continue;
const Coord S0 = o.geom.GetScatteringVector();
const double inv_lambda = 1.0 / o.geom.GetWavelength_A();
for (const auto &r: o.reflections) {
if (r.on_ice_ring || !AcceptReflection(r, d_min_limit_, d_max_limit_) || !(r.d > 0.0f))
continue;
const double w = r.I * r.prescaling_corr * r.qe_corr * r.flight_corr / *o.image_scale_g;
if (!std::isfinite(w))
continue;
const Coord q = (o.latt.Astar() * static_cast<float>(r.h) + o.latt.Bstar() * static_cast<float>(r.k)
+ o.latt.Cstar() * static_cast<float>(r.l)) * static_cast<float>(radial_scale);
const double x = 0.5 / (inv_lambda * r.d * r.d);
pts.push_back({x, VecLen(q.x + S0.x, q.y + S0.y, q.z + S0.z) - inv_lambda, w});
max_x = std::max(max_x, x);
}
}
constexpr int N_SHELLS = 8;
if (pts.size() < 100 * N_SHELLS)
return radial_scale;
std::array<double, N_SHELLS> sw{}, swde{}, swx{};
for (const auto &p: pts) {
const int b = std::min(N_SHELLS - 1, static_cast<int>(p.x / max_x * N_SHELLS));
sw[b] += p.w;
swde[b] += p.w * p.de;
swx[b] += p.w * p.x;
}
double sxy = 0.0, sxx = 0.0;
for (int b = 0; b < N_SHELLS; ++b) {
if (!(sw[b] > 0.0))
continue;
const double x = swx[b] / sw[b], y = swde[b] / sw[b];
sxy += sw[b] * x * y;
sxx += sw[b] * x * x;
}
if (!(sxx > 0.0) || !std::isfinite(sxy))
return radial_scale;
// the slope is eps, removed by scaling q by (1 - eps)
return radial_scale * (1.0 - sxy / sxx);
}
double StillsPartialityRefine::MeasureRadialSpread(const std::vector<IntegrationOutcome> &outcomes,
const RunWidth &width) const {
// Strong spots only: their centroids are good to a fraction of a pixel.
constexpr double MIN_I_OVER_SIGMA = 10.0;
constexpr size_t MIN_SPOTS = 200;
constexpr float STEP = 1e-3f; // of the wavenumber, for the direction a spot moves in
// Per spot: m = how far (px, on the plane) the model moves it per unit s^2, and d = observed - predicted.
struct Spot { double mx, my, dx, dy; };
std::vector<Spot> spots;
for (const auto &o: outcomes) {
if (!o.image_scale_g || !(*o.image_scale_g > 0.0))
continue;
const Coord S0 = o.geom.GetScatteringVector();
for (const auto &r: o.reflections) {
if (r.on_ice_ring || !AcceptReflection(r, d_min_limit_, d_max_limit_) || !(r.d > 0.0f)
|| !(r.I > MIN_I_OVER_SIGMA * r.sigma) || !std::isfinite(r.observed_x) || !std::isfinite(r.observed_y)
|| !std::isfinite(r.dist_ewald))
continue;
const Coord q = o.latt.Astar() * static_cast<float>(r.h) + o.latt.Bstar() * static_cast<float>(r.k)
+ o.latt.Cstar() * static_cast<float>(r.l);
const double dstar = 1.0 / r.d, qz = std::fabs(q.z);
const double a = width.gamma_e * dstar, b = width.bandwidth_sigma * qz;
const double sigma2 = width.gamma0 * width.gamma0 + a * a + b * b;
if (!(sigma2 > 0.0))
continue;
const auto p0 = o.geom.RecipToDetector(q);
const auto p1 = o.geom.RecipToDetector(q + S0 * STEP);
const double f = qz * r.dist_ewald / sigma2 / STEP;
Spot s{f * (p1.first - p0.first), f * (p1.second - p0.second),
r.observed_x - r.predicted_x, r.observed_y - r.predicted_y};
if (std::isfinite(s.mx) && std::isfinite(s.my))
spots.push_back(s);
}
}
if (spots.size() < MIN_SPOTS)
return 0.0;
// Least squares, reweighted against the spots the model does not describe (overlaps, split spots):
// Cauchy weights at three times the typical residual.
double s2 = 0.0;
std::vector<double> r2(spots.size());
for (int iter = 0; iter < 5; ++iter) {
for (size_t i = 0; i < spots.size(); ++i) {
const double ex = spots[i].dx - s2 * spots[i].mx, ey = spots[i].dy - s2 * spots[i].my;
r2[i] = ex * ex + ey * ey;
}
std::vector<double> sorted = r2;
std::nth_element(sorted.begin(), sorted.begin() + sorted.size() / 2, sorted.end());
const double scale2 = 9.0 * sorted[sorted.size() / 2] / 1.386; // median r^2 = 1.386 sigma^2 in 2D
double num = 0.0, den = 0.0;
for (size_t i = 0; i < spots.size(); ++i) {
const double w = 1.0 / (1.0 + r2[i] / scale2);
num += w * (spots[i].mx * spots[i].dx + spots[i].my * spots[i].dy);
den += w * (spots[i].mx * spots[i].mx + spots[i].my * spots[i].my);
}
if (!(den > 0.0))
return 0.0;
s2 = num / den;
}
return std::max(0.0, s2);
}
std::optional<StillsPartialityRefine::RunWidth> StillsPartialityRefine::MeasureRunWidth(
const std::vector<IntegrationOutcome> &outcomes, const std::optional<UnitCell> &reference_cell,
double radial_scale, const RunWidth *window_width) const {
// The rocking width measured on the crystals rather than on the prediction window. A lattice point
// sits anywhere across the window with equal likelihood, while what it records is I_full * p(de), so
// the intensity-weighted second moment of the excitation error, sum I de^2 / sum I, is the width s^2
// of a Gaussian p - corrected for the window cutting the curve's tails (UntruncatedVariance). The
// plain moment of de over the predicted reflections, which the per-crystal fit in RefineOne uses, is
// instead the window's own (W^2 / 3). Measured in shells of d*^2 over the whole run, where the
// intensities of thousands of crystals average out, and fitted as s^2 = gamma0^2 + gamma_e^2 d*^2 +
// (bandwidth_sigma lambda d*^2 / 2)^2.
//
// Each frame predicts through a window of its own (twice its profile radius), and these differ by an
// order of magnitude within a run. Pooled, the frames with the widest windows decide both moments, and
// the correction then reads their window: on a run whose windows are mostly narrower than the curve at
// high resolution, the pooled measurement came out as the window at every resolution, a width constant
// in d* that is several times too wide at low resolution. So within a shell the frames are taken in
// WINDOW_GROUPS groups of similar window, each measured against its own, and the shell's width is the
// median of the groups whose curve is narrower than their window; a shell where no group can see the
// curve is left out.
//
// A frame's window is the largest excitation error it predicted where it predicted through one width.
// Predicted through the run's width (window_width), the window is its formula at the reflection's own
// resolution: the frame's largest excitation error is then the high-resolution window, and taken as the
// window of its low-resolution reflections it put them in the wrong group.
const auto &indexing = experiment_.GetIndexingSettings();
struct Point { double x, de2, w, var_w, window; };
std::vector<Point> pts;
for (const auto &o: outcomes) {
if (!o.image_scale_g || !(*o.image_scale_g > 0.0))
continue;
if (reference_cell && !o.latt.GetUnitCell().is_close(*reference_cell, indexing.GetUnitCellDistTolerance(),
indexing.GetUnitCellAngleTolerance_deg()))
continue;
float frame_window = 0.0f; // the largest excitation error the frame predicted
for (const auto &r: o.reflections)
if (std::isfinite(r.dist_ewald))
frame_window = std::max(frame_window, std::fabs(r.dist_ewald));
for (const auto &r: o.reflections) {
if (r.on_ice_ring || !AcceptReflection(r, d_min_limit_, d_max_limit_))
continue;
const double corr = r.prescaling_corr * r.qe_corr * r.flight_corr / *o.image_scale_g;
const double w = r.I * corr, sigma_w = r.sigma * corr;
if (!std::isfinite(w) || !std::isfinite(sigma_w) || !std::isfinite(r.dist_ewald) || !(r.d > 0.0f))
continue;
// The excitation error the window was cut in is the prediction's; the curve's is taken at the
// run's radial scale (MeasureRadialScale), recomputed from the lattice when that is not one.
double de = r.dist_ewald;
if (radial_scale != 1.0) {
const Coord q = (o.latt.Astar() * static_cast<float>(r.h) + o.latt.Bstar() * static_cast<float>(r.k)
+ o.latt.Cstar() * static_cast<float>(r.l)) * static_cast<float>(radial_scale);
const Coord S0 = o.geom.GetScatteringVector();
de = VecLen(q.x + S0.x, q.y + S0.y, q.z + S0.z) - 1.0 / o.geom.GetWavelength_A();
}
double window = frame_window;
if (window_width) {
// the formula at the reflection's d*, its bandwidth term at |q_z| = lambda d*^2 / 2
const double dstar = 1.0 / r.d;
const double a = window_width->gamma_e * dstar;
const double b = window_width->bandwidth_sigma * o.geom.GetWavelength_A() * dstar * dstar / 2.0;
window = std::sqrt(window_width->gamma0 * window_width->gamma0 + a * a + b * b);
}
pts.push_back({1.0 / (static_cast<double>(r.d) * r.d), de * de, w, sigma_w * sigma_w, window});
}
}
constexpr size_t N_SHELLS = 8;
constexpr size_t WINDOW_GROUPS = 4;
if (pts.size() < 100 * N_SHELLS)
return std::nullopt;
std::sort(pts.begin(), pts.end(), [](const Point &a, const Point &b) { return a.x < b.x; });
Logger logger("StillsPartialityRefine");
// A group's moment is no better than the summed intensity it is weighted by, so a group is used only
// where that sum is measured to 10 % (sum I / sigma(sum I) >= 10): beyond the diffraction limit the
// sum is noise and can even be negative, and says nothing about the width.
constexpr double MIN_SHELL_SIGNAL = 10.0;
// The width of the points [lo, hi) of pts (sorted by d*): the median of the window groups' widths.
auto shell_width = [&](size_t lo, size_t hi) -> std::optional<double> {
std::vector<Point> shell(pts.begin() + lo, pts.begin() + hi);
std::sort(shell.begin(), shell.end(), [](const Point &a, const Point &b) { return a.window < b.window; });
std::vector<double> widths;
for (size_t g = 0; g < WINDOW_GROUPS; ++g) {
const size_t glo = g * shell.size() / WINDOW_GROUPS, ghi = (g + 1) * shell.size() / WINDOW_GROUPS;
double sw = 0.0, svar = 0.0, swde2 = 0.0, sde2 = 0.0;
for (size_t i = glo; i < ghi; ++i) {
sw += shell[i].w;
svar += shell[i].var_w;
swde2 += shell[i].w * shell[i].de2;
sde2 += shell[i].de2;
}
if (!(sw >= MIN_SHELL_SIGNAL * std::sqrt(svar)) || !(swde2 > 0.0))
continue;
if (const auto v = UntruncatedVariance(swde2 / sw, sde2 / static_cast<double>(ghi - glo)))
widths.push_back(*v);
}
if (widths.empty())
return std::nullopt;
std::sort(widths.begin(), widths.end());
const size_t m = widths.size();
return m % 2 ? widths[m / 2] : 0.5 * (widths[m / 2 - 1] + widths[m / 2]);
};
// For the three-term formula (the prediction window): shells of equal count in d*^2.
std::vector<double> sx, sy;
for (size_t k = 0; k < N_SHELLS; ++k) {
const size_t lo = k * pts.size() / N_SHELLS, hi = (k + 1) * pts.size() / N_SHELLS;
const auto y = shell_width(lo, hi);
if (!y)
continue;
double sumx = 0.0;
for (size_t i = lo; i < hi; ++i)
sumx += pts[i].x;
const double x = sumx / static_cast<double>(hi - lo);
sx.push_back(x);
sy.push_back(*y);
logger.Debug("Stills rocking width at d = {:.2f} A: {:.2e} 1/A ({:.3f} deg)",
1.0 / std::sqrt(x), std::sqrt(*y), std::sqrt(*y / x) * kRadToDeg);
}
// For the partiality: shells of equal width in d*, kept as a table. Equal-count shells crowd where
// the reflections are - on a run predicting ~1000 reflections a frame, all eight sat at 3.8-1.8 A, so
// the low-resolution width was the formula's extrapolation, and the three-term fit flipped between
// forms with the number of frames (to a pure bandwidth at 50k frames). Measured where it is used and
// interpolated, the width needs no form. A wider curve at finer resolution is the physics (every term
// grows with d*), so the table is made non-decreasing (pool adjacent violators, weighted by the
// shells' summed signal).
std::vector<double> table_dstar, table_s, table_weight;
{
const double lo_d = std::sqrt(pts.front().x), hi_d = std::sqrt(pts.back().x);
size_t lo = 0;
for (size_t k = 0; k < N_SHELLS; ++k) {
const double edge = lo_d + (hi_d - lo_d) * static_cast<double>(k + 1) / N_SHELLS;
size_t hi = lo;
while (hi < pts.size() && (k + 1 == N_SHELLS || std::sqrt(pts[hi].x) < edge))
++hi;
double sw = 0.0, svar = 0.0, sds = 0.0;
for (size_t i = lo; i < hi; ++i) {
sw += pts[i].w;
svar += pts[i].var_w;
sds += std::sqrt(pts[i].x);
}
if (hi - lo >= 400 && sw >= MIN_SHELL_SIGNAL * std::sqrt(svar))
if (const auto y = shell_width(lo, hi)) {
table_dstar.push_back(sds / static_cast<double>(hi - lo));
table_s.push_back(std::sqrt(*y));
table_weight.push_back(sw / std::sqrt(svar));
}
lo = hi;
}
std::vector<double> block_s, block_w;
std::vector<size_t> block_n;
for (size_t i = 0; i < table_s.size(); ++i) {
block_s.push_back(table_s[i]);
block_w.push_back(table_weight[i]);
block_n.push_back(1);
while (block_s.size() > 1 && block_s[block_s.size() - 2] > block_s.back()) {
const size_t j = block_s.size() - 2;
block_s[j] = (block_s[j] * block_w[j] + block_s.back() * block_w.back()) / (block_w[j] + block_w.back());
block_w[j] += block_w.back();
block_n[j] += block_n.back();
block_s.pop_back();
block_w.pop_back();
block_n.pop_back();
}
}
table_s.clear();
for (size_t j = 0; j < block_s.size(); ++j)
table_s.insert(table_s.end(), block_n[j], block_s[j]);
if (table_dstar.size() < 3) {
table_dstar.clear();
table_s.clear();
}
}
if (sx.size() < 3)
return std::nullopt;
// Least squares for s^2 = A + B d*^2 + C d*^4 over the shells. Every term is a variance, so a negative
// one is unphysical: of the fits on each subset of the three terms, the best with none negative is kept.
std::array<double, 3> best{};
double best_residual = INFINITY;
for (int mask = 1; mask < 8; ++mask) {
std::vector<int> terms;
for (int t = 0; t < 3; ++t)
if (mask & (1 << t))
terms.push_back(t);
const int m = static_cast<int>(terms.size());
Eigen::MatrixXd M = Eigen::MatrixXd::Zero(m, m);
Eigen::VectorXd v = Eigen::VectorXd::Zero(m);
for (size_t k = 0; k < sx.size(); ++k)
for (int i = 0; i < m; ++i) {
const double fi = std::pow(sx[k], terms[i]);
v(i) += fi * sy[k];
for (int j = 0; j < m; ++j)
M(i, j) += fi * std::pow(sx[k], terms[j]);
}
const Eigen::VectorXd c = M.ldlt().solve(v);
if (!c.allFinite() || (c.array() < 0.0).any())
continue;
std::array<double, 3> coef{};
for (int i = 0; i < m; ++i)
coef[terms[i]] = c(i);
double residual = 0.0;
for (size_t k = 0; k < sx.size(); ++k) {
const double r = sy[k] - coef[0] - coef[1] * sx[k] - coef[2] * sx[k] * sx[k];
residual += r * r;
}
if (residual < best_residual) {
best_residual = residual;
best = coef;
}
}
if (!std::isfinite(best_residual) || !(best[0] + best[1] + best[2] > 0.0))
return std::nullopt;
// The d*^4 term is a bandwidth: its radial smear bw |q_z|, with |q_z| = lambda d*^2 / 2 on the sphere.
const RunWidth width{.gamma0 = std::sqrt(best[0]), .gamma_e = std::sqrt(best[1]),
.bandwidth_sigma = 2.0 * std::sqrt(best[2]) / experiment_.GetWavelength_A(),
.radial_scale = radial_scale, .table_dstar = table_dstar, .table_s = table_s};
logger.Info("Stills rocking width measured: {:.2e} 1/A + {:.3f} deg angular + {:.4f} bandwidth (FWHM)",
width.gamma0, width.gamma_e * kRadToDeg, width.bandwidth_sigma * 2.3548);
std::string table;
for (size_t i = 0; i < table_dstar.size(); ++i)
table += fmt::format(" {:.2f} A {:.2e}", 1.0 / table_dstar[i], table_s[i]);
logger.Info("Stills rocking width for the partiality, against resolution (1/A):{}",
table.empty() ? " none, the formula is used" : table);
return width;
}
StillsPartialityRefine::RunWidth StillsPartialityRefine::BalanceRunWidth(
const std::vector<IntegrationOutcome> &outcomes, const std::map<HKLKey, double> &reference,
const std::optional<UnitCell> &reference_cell, const RunWidth &width, size_t nthreads) const {
// The width table is measured from moments of the excitation error through the prediction window, and
// the tails of the curve are where that is least sure: on rotation sweeps processed as stills, the
// reflections recorded at under a third of their peak came out 30% fainter than the model at low
// resolution and up to 50% brighter at high resolution, against those recorded near their peak. So
// each shell of the table is scaled by the factor s at which its reflections predicted below half
// their peak and those above it put the same scale on the merged intensities:
// sum I / sum p_s I_ref is the same for both, p_s the Gaussian of width s sigma.
if (width.table_dstar.empty())
return width;
const auto &indexing = experiment_.GetIndexingSettings();
struct Point { double u, x, ref; }; // eps / sigma, I / G (corrected), the reference intensity
struct ShellPoint { size_t shell; Point p; };
const Width w{.gamma0 = width.gamma0, .gamma_e = width.gamma_e, .bw = width.bandwidth_sigma,
.table_dstar = &width.table_dstar, .table_s = &width.table_s};
// Each frame's points on the workers, then dealt into the shells in frame order, so every sum below runs
// in the order of the serial loop.
std::vector<std::vector<ShellPoint>> per_frame(outcomes.size());
ParallelFor(static_cast<int>(outcomes.size()), nthreads, [&](int i) {
const auto &o = outcomes[i];
if (!o.image_scale_g || !(*o.image_scale_g > 0.0))
return;
if (reference_cell && !o.latt.GetUnitCell().is_close(*reference_cell, indexing.GetUnitCellDistTolerance(),
indexing.GetUnitCellAngleTolerance_deg()))
return;
const Coord S0 = o.geom.GetScatteringVector();
const double inv_lambda = 1.0 / o.geom.GetWavelength_A();
for (const auto &r: o.reflections) {
if (r.on_ice_ring || !AcceptReflection(r, d_min_limit_, d_max_limit_) || !std::isfinite(r.I))
continue;
const auto it = reference.find(hkl_key_generator_(r));
if (it == reference.end() || !(it->second > 0.0))
continue;
const Coord q = (o.latt.Astar() * static_cast<float>(r.h) + o.latt.Bstar() * static_cast<float>(r.k)
+ o.latt.Cstar() * static_cast<float>(r.l)) * static_cast<float>(width.radial_scale);
const double dstar = VecLen(q.x, q.y, q.z);
const double de = VecLen(q.x + S0.x, q.y + S0.y, q.z + S0.z) - inv_lambda;
const double x = r.I * r.prescaling_corr * r.qe_corr * r.flight_corr / *o.image_scale_g;
if (!std::isfinite(x))
continue;
// the table shell nearest in d*
size_t k = std::upper_bound(width.table_dstar.begin(), width.table_dstar.end(), dstar)
- width.table_dstar.begin();
if (k == width.table_dstar.size() || (k > 0 && dstar - width.table_dstar[k - 1] < width.table_dstar[k] - dstar))
k = k > 0 ? k - 1 : 0;
per_frame[i].push_back({k, {de / std::sqrt(w.Sigma2(dstar, q.z)), x, it->second}});
}
});
std::vector<std::vector<Point>> shells(width.table_dstar.size());
for (auto &f: per_frame) {
for (const auto &sp: f)
shells[sp.shell].push_back(sp.p);
f = {};
}
// log(sum I / sum p_s I_ref) over the reflections below half the table's peak, less the same over those
// above it; falls as s grows.
auto gap = [](const std::vector<Point> &pts, double s) {
const double half = std::sqrt(2.0 * std::log(2.0)); // |u| at half the peak
double x_lo = 0.0, m_lo = 0.0, x_hi = 0.0, m_hi = 0.0;
for (const auto &p: pts) {
const double ps = std::exp(-0.5 * p.u * p.u / (s * s));
(std::fabs(p.u) > half ? x_lo : x_hi) += p.x;
(std::fabs(p.u) > half ? m_lo : m_hi) += ps * p.ref;
}
if (!(x_lo > 0.0 && m_lo > 0.0 && x_hi > 0.0 && m_hi > 0.0))
return std::numeric_limits<double>::quiet_NaN();
return std::log(x_lo / m_lo) - std::log(x_hi / m_hi);
};
// Each shell on its own worker.
std::vector<double> factor(shells.size(), NAN);
ParallelFor(static_cast<int>(shells.size()), nthreads, [&](int k) {
double lo = 1.0 / BALANCE_RANGE, hi = BALANCE_RANGE;
const double g_lo = gap(shells[k], lo), g_hi = gap(shells[k], hi);
if (shells[k].size() < 400 || !(g_lo > 0.0) || !(g_hi < 0.0))
return;
for (int i = 0; i < 20; ++i) { // the factor to 2e-6
const double mid = std::sqrt(lo * hi);
(gap(shells[k], mid) > 0.0 ? lo : hi) = mid;
}
factor[k] = std::sqrt(lo * hi);
});
RunWidth balanced = width;
std::string table;
for (size_t k = 0; k < shells.size(); ++k) {
if (std::isnan(factor[k]))
continue;
balanced.table_s[k] *= factor[k];
table += fmt::format(" {:.2f} A x{:.2f}", 1.0 / width.table_dstar[k], factor[k]);
}
Logger("StillsPartialityRefine").Info("Stills rocking width balanced on the partials, against resolution:{}",
table.empty() ? " unchanged" : table);
return balanced;
}
StillsPartialityRefine::CrystalPrior StillsPartialityRefine::RunPrior(const std::vector<CrystalFit> &fits) const {
// The spread of a parameter over the crystals: the variance of the estimates less the median variance
// they carry from their own data, floored at a small value (a crystal is never held exactly).
auto spread = [&](auto value, auto variance, double floor) {
std::vector<double> x, v;
for (const auto &f: fits)
if (f.refined && std::isfinite(variance(f)) && variance(f) > 0.0) {
x.push_back(value(f));
v.push_back(variance(f));
}
if (x.size() < 10)
return floor;
double mean = 0.0;
for (double e: x)
mean += e;
mean /= static_cast<double>(x.size());
double var = 0.0;
for (double e: x)
var += (e - mean) * (e - mean);
var /= static_cast<double>(x.size() - 1);
std::nth_element(v.begin(), v.begin() + v.size() / 2, v.end());
return std::max(floor, std::sqrt(std::max(0.0, var - v[v.size() / 2])));
};
const CrystalPrior prior{
.sigma_eta = spread([](const CrystalFit &f) { return f.eta; },
[](const CrystalFit &f) { return f.var_eta; }, MIN_PRIOR_ETA),
.sigma_ln_width = spread([](const CrystalFit &f) { return f.ln_width; },
[](const CrystalFit &f) { return f.var_ln_width; }, MIN_PRIOR_LN_WIDTH)};
Logger("StillsPartialityRefine").Info("Stills crystals differ in radial scale by {:.1e} and in rocking width "
"by {:.0f}% (sd over the crystals, net of their own uncertainty)",
prior.sigma_eta, 100.0 * prior.sigma_ln_width);
return prior;
}
double StillsPartialityRefine::Run(std::vector<IntegrationOutcome> &outcomes, size_t nthreads,
const std::optional<UnitCell> &reference_cell,
const std::optional<RunWidth> &given_width,
std::optional<RunWidth> *used_width,
std::optional<CrystalPrior> *used_prior) const {
const auto &indexing = experiment_.GetIndexingSettings();
auto merged_crystal = [&](const IntegrationOutcome &o) {
return !reference_cell || o.latt.GetUnitCell().is_close(*reference_cell,
indexing.GetUnitCellDistTolerance(),
indexing.GetUnitCellAngleTolerance_deg());
};
if (nthreads == 0)
nthreads = AvailableCpus();
nthreads = std::max<size_t>(1, nthreads);
// Where the frames were predicted through a curve measured before the image pass, the partialities use
// that same curve. Measured again here, through windows that follow it, the width reads narrower at low
// resolution (its constant term falls to about zero), and the merge it gave moved R-free against the
// models by up to +-0.015 per run in both directions, where the one curve moved it by at most +0.008.
std::optional<RunWidth> run_width = given_width;
if (!run_width) {
double radial_scale = 1.0;
for (int i = 0; i < 3; ++i)
radial_scale = MeasureRadialScale(outcomes, reference_cell, radial_scale);
Logger("StillsPartialityRefine").Info("Stills rocking curve centre: reciprocal lattice scaled by {:+.2e}",
radial_scale - 1.0);
run_width = MeasureRunWidth(outcomes, reference_cell, radial_scale);
}
const double radial_scale = run_width ? run_width->radial_scale : 1.0;
// The priors on a crystal's radial scale and width are the run's own spread of them: the first cycle
// refines every crystal against loose priors, and the spread of those estimates less their own
// uncertainty (method of moments) is how much crystals really differ. On an XFEL each shot has its
// photon energy and the spread is large; on a monochromatic or a stable pink beam it comes out small,
// and the crystals are held to the run's curve.
CrystalPrior prior{.sigma_eta = settings_.max_eta, .sigma_ln_width = settings_.max_ln_width};
std::vector<CrystalFit> fits(outcomes.size());
for (int outer = 0; outer < settings_.outer_iterations; ++outer) {
// Reference full intensities from the current corrections.
const std::vector<MergedReflection> merged = MergeAll(experiment_, outcomes, nthreads, reference_cell);
std::map<HKLKey, double> reference;
for (const auto &m: merged)
reference[hkl_key_generator_(m)] = m.I;
if (outer == 0 && run_width)
run_width = BalanceRunWidth(outcomes, reference, reference_cell, *run_width, nthreads);
std::atomic<size_t> next{0};
auto worker = [&]() {
size_t i = next.fetch_add(1);
while (i < outcomes.size()) {
fits[i] = merged_crystal(outcomes[i]) ? RefineOne(outcomes[i], reference, run_width, radial_scale, prior)
: CrystalFit{};
i = next.fetch_add(1);
}
};
const size_t nt = std::min(nthreads, std::max<size_t>(1, outcomes.size()));
if (nt <= 1) {
worker();
} else {
std::vector<std::future<void>> futures;
futures.reserve(nt);
for (size_t t = 0; t < nt; ++t)
futures.emplace_back(std::async(std::launch::async, worker));
for (auto &f: futures)
f.get();
}
if (outer == 0)
prior = RunPrior(fits);
}
if (used_width)
*used_width = run_width;
if (used_prior)
*used_prior = prior;
double tilt_sum = 0.0;
size_t tilt_n = 0;
for (const auto &f: fits)
if (f.refined) {
tilt_sum += f.tilt_deg;
++tilt_n;
}
const double last_mean_tilt = tilt_n > 0 ? tilt_sum / static_cast<double>(tilt_n) : 0.0;
return last_mean_tilt;
}
void StillsPartialityRefine::RefineAgainst(std::vector<IntegrationOutcome> &outcomes, size_t nthreads,
const std::optional<UnitCell> &reference_cell,
const std::vector<MergedReflection> &reference,
const RunWidth &run_width, const CrystalPrior &prior) const {
const auto &indexing = experiment_.GetIndexingSettings();
std::map<HKLKey, double> reference_map;
for (const auto &m: reference)
reference_map[hkl_key_generator_(m)] = m.I;
const std::optional<RunWidth> width = run_width;
ParallelFor(static_cast<int>(outcomes.size()), std::max<size_t>(1, nthreads), [&](int i) {
auto &o = outcomes[i];
if (!reference_cell || o.latt.GetUnitCell().is_close(*reference_cell, indexing.GetUnitCellDistTolerance(),
indexing.GetUnitCellAngleTolerance_deg()))
RefineOne(o, reference_map, width, run_width.radial_scale, prior);
});
}