gridder_cxx.h 35.2 KB
Newer Older
Martin Reinecke's avatar
Martin Reinecke committed
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
#ifndef GRIDDER_CXX_H
#define GRIDDER_CXX_H

/*
 *  This file is part of nifty_gridder.
 *
 *  nifty_gridder is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  nifty_gridder is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with nifty_gridder; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

22
/* Copyright (C) 2019-2020 Max-Planck-Society
Martin Reinecke's avatar
Martin Reinecke committed
23 24 25 26 27 28 29 30
   Author: Martin Reinecke */

#include <iostream>
#include <algorithm>
#include <cstdlib>
#include <cmath>
#include <vector>
#include <array>
Martin Reinecke's avatar
Martin Reinecke committed
31
#include <memory>
Martin Reinecke's avatar
Martin Reinecke committed
32

Martin Reinecke's avatar
Martin Reinecke committed
33 34 35 36 37
#include "ducc0/infra/error_handling.h"
#include "ducc0/math/fft.h"
#include "ducc0/infra/threading.h"
#include "ducc0/infra/useful_macros.h"
#include "ducc0/infra/mav.h"
Martin Reinecke's avatar
Martin Reinecke committed
38
#include "ducc0/infra/simd.h"
Martin Reinecke's avatar
Martin Reinecke committed
39
#include "ducc0/math/gridding_kernel.h"
Martin Reinecke's avatar
Martin Reinecke committed
40

Martin Reinecke's avatar
Martin Reinecke committed
41
namespace ducc0 {
Martin Reinecke's avatar
Martin Reinecke committed
42

Martin Reinecke's avatar
Martin Reinecke committed
43
namespace detail_gridder {
Martin Reinecke's avatar
Martin Reinecke committed
44 45 46 47 48

using namespace std;

template<size_t ndim> void checkShape
  (const array<size_t, ndim> &shp1, const array<size_t, ndim> &shp2)
49
  { MR_assert(shp1==shp2, "shape mismatch"); }
Martin Reinecke's avatar
Martin Reinecke committed
50 51 52 53 54 55 56 57 58

template<typename T> inline T fmod1 (T v)
  { return v-floor(v); }

//
// Start of real gridder functionality
//

template<typename T> void complex2hartley
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
59
  (const mav<complex<T>, 2> &grid, mav<T,2> &grid2, size_t nthreads)
Martin Reinecke's avatar
Martin Reinecke committed
60
  {
61
  MR_assert(grid.conformable(grid2), "shape mismatch");
Martin Reinecke's avatar
Martin Reinecke committed
62 63 64 65 66 67 68 69 70 71
  size_t nu=grid.shape(0), nv=grid.shape(1);

  execStatic(nu, nthreads, 0, [&](Scheduler &sched)
    {
    while (auto rng=sched.getNext()) for(auto u=rng.lo; u<rng.hi; ++u)
      {
      size_t xu = (u==0) ? 0 : nu-u;
      for (size_t v=0; v<nv; ++v)
        {
        size_t xv = (v==0) ? 0 : nv-v;
Martin Reinecke's avatar
Martin Reinecke committed
72 73
        grid2.v(u,v) = T(0.5)*(grid( u, v).real()+grid( u, v).imag()+
                               grid(xu,xv).real()-grid(xu,xv).imag());
Martin Reinecke's avatar
Martin Reinecke committed
74 75 76 77 78 79
        }
      }
    });
  }

template<typename T> void hartley2complex
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
80
  (const mav<T,2> &grid, mav<complex<T>,2> &grid2, size_t nthreads)
Martin Reinecke's avatar
Martin Reinecke committed
81
  {
82
  MR_assert(grid.conformable(grid2), "shape mismatch");
Martin Reinecke's avatar
Martin Reinecke committed
83 84 85 86 87 88 89 90 91 92 93 94
  size_t nu=grid.shape(0), nv=grid.shape(1);

  execStatic(nu, nthreads, 0, [&](Scheduler &sched)
    {
    while (auto rng=sched.getNext()) for(auto u=rng.lo; u<rng.hi; ++u)
      {
      size_t xu = (u==0) ? 0 : nu-u;
      for (size_t v=0; v<nv; ++v)
        {
        size_t xv = (v==0) ? 0 : nv-v;
        T v1 = T(0.5)*grid( u, v);
        T v2 = T(0.5)*grid(xu,xv);
Martin Reinecke's avatar
Martin Reinecke committed
95
        grid2.v(u,v) = std::complex<T>(v1+v2, v1-v2);
Martin Reinecke's avatar
Martin Reinecke committed
96 97 98 99 100
        }
      }
    });
  }

Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
101 102
template<typename T> void hartley2_2D(const mav<T,2> &in,
  mav<T,2> &out, size_t nthreads)
Martin Reinecke's avatar
Martin Reinecke committed
103
  {
104
  MR_assert(in.conformable(out), "shape mismatch");
Martin Reinecke's avatar
Martin Reinecke committed
105
  size_t nu=in.shape(0), nv=in.shape(1);
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
106 107
  fmav<T> fin(in), fout(out);
  r2r_separable_hartley(fin, fout, {0,1}, T(1), nthreads);
Martin Reinecke's avatar
Martin Reinecke committed
108 109 110 111 112
  execStatic((nu+1)/2-1, nthreads, 0, [&](Scheduler &sched)
    {
    while (auto rng=sched.getNext()) for(auto i=rng.lo+1; i<rng.hi+1; ++i)
      for(size_t j=1; j<(nv+1)/2; ++j)
         {
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
113 114 115 116
         T a = out(i,j);
         T b = out(nu-i,j);
         T c = out(i,nv-j);
         T d = out(nu-i,nv-j);
Martin Reinecke's avatar
Martin Reinecke committed
117 118 119 120
         out.v(i,j) = T(0.5)*(a+b+c-d);
         out.v(nu-i,j) = T(0.5)*(a+b+d-c);
         out.v(i,nv-j) = T(0.5)*(a+c+d-b);
         out.v(nu-i,nv-j) = T(0.5)*(b+c+d-a);
Martin Reinecke's avatar
Martin Reinecke committed
121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156
         }
     });
  }

using idx_t = uint32_t;

struct RowChan
  {
  idx_t row, chan;
  };

struct UVW
  {
  double u, v, w;
  UVW() {}
  UVW(double u_, double v_, double w_) : u(u_), v(v_), w(w_) {}
  UVW operator* (double fct) const
    { return UVW(u*fct, v*fct, w*fct); }
  void Flip() { u=-u; v=-v; w=-w; }
  bool FixW()
    {
    bool flip = w<0;
    if (flip) Flip();
    return flip;
    }
  };

class Baselines
  {
  protected:
    vector<UVW> coord;
    vector<double> f_over_c;
    idx_t nrows, nchan;
    idx_t shift, mask;

  public:
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
157 158
    template<typename T> Baselines(const mav<T,2> &coord_,
      const mav<T,1> &freq, bool negate_v=false)
Martin Reinecke's avatar
Martin Reinecke committed
159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174
      {
      constexpr double speedOfLight = 299792458.;
      MR_assert(coord_.shape(1)==3, "dimension mismatch");
      auto hugeval = size_t(~(idx_t(0)));
      MR_assert(coord_.shape(0)<hugeval, "too many entries in MS");
      MR_assert(coord_.shape(1)<hugeval, "too many entries in MS");
      MR_assert(coord_.size()<hugeval, "too many entries in MS");
      nrows = coord_.shape(0);
      nchan = freq.shape(0);
      shift=0;
      while((idx_t(1)<<shift)<nchan) ++shift;
      mask=(idx_t(1)<<shift)-1;
      MR_assert(nrows*(mask+1)<hugeval, "too many entries in MS");
      f_over_c.resize(nchan);
      for (size_t i=0; i<nchan; ++i)
        {
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
175
        MR_assert(freq(i)>0, "negative channel frequency encountered");
Martin Reinecke's avatar
Martin Reinecke committed
176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199
        f_over_c[i] = freq(i)/speedOfLight;
        }
      coord.resize(nrows);
      if (negate_v)
        for (size_t i=0; i<coord.size(); ++i)
          coord[i] = UVW(coord_(i,0), -coord_(i,1), coord_(i,2));
      else
        for (size_t i=0; i<coord.size(); ++i)
          coord[i] = UVW(coord_(i,0), coord_(i,1), coord_(i,2));
      }

    RowChan getRowChan(idx_t index) const
      { return RowChan{index>>shift, index&mask}; }

    UVW effectiveCoord(const RowChan &rc) const
      { return coord[rc.row]*f_over_c[rc.chan]; }
    UVW effectiveCoord(idx_t index) const
      { return effectiveCoord(getRowChan(index)); }
    size_t Nrows() const { return nrows; }
    size_t Nchannels() const { return nchan; }
    idx_t getIdx(idx_t irow, idx_t ichan) const
      { return ichan+(irow<<shift); }
  };

Martin Reinecke's avatar
Martin Reinecke committed
200
template<typename T> class GridderConfig
Martin Reinecke's avatar
Martin Reinecke committed
201 202 203
  {
  protected:
    size_t nx_dirty, ny_dirty, nu, nv;
Martin Reinecke's avatar
Martin Reinecke committed
204 205
    double ofactor;

Martin Reinecke's avatar
Martin Reinecke committed
206
  // FIXME: this should probably be done more cleanly
Martin Reinecke's avatar
Martin Reinecke committed
207 208 209 210 211
  public:
    shared_ptr<GriddingKernel<T>> krn;

  protected:
    double psx, psy;
Martin Reinecke's avatar
Martin Reinecke committed
212 213 214 215 216 217
    size_t supp, nsafe;
    double beta;
    size_t nthreads;
    double ushift, vshift;
    int maxiu0, maxiv0;

Martin Reinecke's avatar
Martin Reinecke committed
218
    complex<T> wscreen(T x, T y, T w, bool adjoint) const
Martin Reinecke's avatar
Martin Reinecke committed
219 220 221 222 223 224 225 226 227 228 229 230 231 232 233
      {
      constexpr T pi = T(3.141592653589793238462643383279502884197);
      T tmp = 1-x-y;
      if (tmp<=0) return 1; // no phase factor beyond the horizon
      T nm1 = (-x-y)/(sqrt(tmp)+1); // more accurate form of sqrt(1-x-y)-1
      T phase = 2*pi*w*nm1;
      if (adjoint) phase *= -1;
      return complex<T>(cos(phase), sin(phase));
      }

  public:
    GridderConfig(size_t nxdirty, size_t nydirty, size_t nu_, size_t nv_,
      double epsilon, double pixsize_x, double pixsize_y, size_t nthreads_)
      : nx_dirty(nxdirty), ny_dirty(nydirty), nu(nu_), nv(nv_),
        ofactor(min(double(nu)/nxdirty, double(nv)/nydirty)),
Martin Reinecke's avatar
Martin Reinecke committed
234
        krn(selectNESKernel<T>(ofactor, epsilon)),
Martin Reinecke's avatar
Martin Reinecke committed
235
        psx(pixsize_x), psy(pixsize_y),
Martin Reinecke's avatar
Martin Reinecke committed
236
        supp(krn->support()), nsafe((supp+1)/2),
Martin Reinecke's avatar
Martin Reinecke committed
237 238
        nthreads(nthreads_),
        ushift(supp*(-0.5)+1+nu), vshift(supp*(-0.5)+1+nv),
Martin Reinecke's avatar
Martin Reinecke committed
239
        maxiu0((nu+nsafe)-supp), maxiv0((nv+nsafe)-supp)
Martin Reinecke's avatar
Martin Reinecke committed
240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265
      {
      MR_assert(nu>=2*nsafe, "nu too small");
      MR_assert(nv>=2*nsafe, "nv too small");
      MR_assert((nx_dirty&1)==0, "nx_dirty must be even");
      MR_assert((ny_dirty&1)==0, "ny_dirty must be even");
      MR_assert((nu&1)==0, "nu must be even");
      MR_assert((nv&1)==0, "nv must be even");
      MR_assert(epsilon>0, "epsilon must be positive");
      MR_assert(pixsize_x>0, "pixsize_x must be positive");
      MR_assert(pixsize_y>0, "pixsize_y must be positive");
      }
    GridderConfig(size_t nxdirty, size_t nydirty,
      double epsilon, double pixsize_x, double pixsize_y, size_t nthreads_)
      : GridderConfig(nxdirty, nydirty, max<size_t>(30,2*nxdirty),
                      max<size_t>(30,2*nydirty), epsilon, pixsize_x,
                      pixsize_y, nthreads_) {}
    size_t Nxdirty() const { return nx_dirty; }
    size_t Nydirty() const { return ny_dirty; }
    double Pixsize_x() const { return psx; }
    double Pixsize_y() const { return psy; }
    size_t Nu() const { return nu; }
    size_t Nv() const { return nv; }
    size_t Supp() const { return supp; }
    size_t Nsafe() const { return nsafe; }
    size_t Nthreads() const { return nthreads; }

Martin Reinecke's avatar
Martin Reinecke committed
266
    void grid2dirty_post(mav<T,2> &tmav,
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
267
      mav<T,2> &dirty) const
Martin Reinecke's avatar
Martin Reinecke committed
268
      {
269
      checkShape(dirty.shape(), {nx_dirty, ny_dirty});
Martin Reinecke's avatar
Martin Reinecke committed
270 271
      auto cfu = krn->corfunc(nx_dirty/2+1, 1./nu, nthreads);
      auto cfv = krn->corfunc(ny_dirty/2+1, 1./nv, nthreads);
Martin Reinecke's avatar
Martin Reinecke committed
272 273 274 275 276 277 278 279 280 281 282 283 284 285
      execStatic(nx_dirty, nthreads, 0, [&](Scheduler &sched)
        {
        while (auto rng=sched.getNext()) for(auto i=rng.lo; i<rng.hi; ++i)
          {
          int icfu = abs(int(nx_dirty/2)-int(i));
          for (size_t j=0; j<ny_dirty; ++j)
            {
            int icfv = abs(int(ny_dirty/2)-int(j));
            size_t i2 = nu-nx_dirty/2+i;
            if (i2>=nu) i2-=nu;
            size_t j2 = nv-ny_dirty/2+j;
            if (j2>=nv) j2-=nv;
            // FIXME: for some reason g++ warns about double-to-float conversion
            // here, even though there is an explicit cast...
Martin Reinecke's avatar
Martin Reinecke committed
286
            dirty.v(i,j) = tmav(i2,j2)*T(cfu[icfu]*cfv[icfv]);
Martin Reinecke's avatar
Martin Reinecke committed
287 288 289 290
            }
          }
        });
      }
Martin Reinecke's avatar
Martin Reinecke committed
291
    void grid2dirty_post2(
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
292
      mav<complex<T>,2> &tmav, mav<T,2> &dirty, T w) const
Martin Reinecke's avatar
Martin Reinecke committed
293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310
      {
      checkShape(dirty.shape(), {nx_dirty,ny_dirty});
      double x0 = -0.5*nx_dirty*psx,
             y0 = -0.5*ny_dirty*psy;
      execStatic(nx_dirty/2+1, nthreads, 0, [&](Scheduler &sched)
        {
        while (auto rng=sched.getNext()) for(auto i=rng.lo; i<rng.hi; ++i)
          {
          T fx = T(x0+i*psx);
          fx *= fx;
          for (size_t j=0; j<=ny_dirty/2; ++j)
            {
            T fy = T(y0+j*psy);
            auto ws = wscreen(fx, fy*fy, w, true);
            size_t ix = nu-nx_dirty/2+i;
            if (ix>=nu) ix-=nu;
            size_t jx = nv-ny_dirty/2+j;
            if (jx>=nv) jx-=nv;
Martin Reinecke's avatar
Martin Reinecke committed
311
            dirty.v(i,j) += (tmav(ix,jx)*ws).real(); // lower left
Martin Reinecke's avatar
Martin Reinecke committed
312 313 314 315 316 317 318
            size_t i2 = nx_dirty-i, j2 = ny_dirty-j;
            size_t ix2 = nu-nx_dirty/2+i2;
            if (ix2>=nu) ix2-=nu;
            size_t jx2 = nv-ny_dirty/2+j2;
            if (jx2>=nv) jx2-=nv;
            if ((i>0)&&(i<i2))
              {
Martin Reinecke's avatar
Martin Reinecke committed
319
              dirty.v(i2,j) += (tmav(ix2,jx)*ws).real(); // lower right
Martin Reinecke's avatar
Martin Reinecke committed
320
              if ((j>0)&&(j<j2))
Martin Reinecke's avatar
Martin Reinecke committed
321
                dirty.v(i2,j2) += (tmav(ix2,jx2)*ws).real(); // upper right
Martin Reinecke's avatar
Martin Reinecke committed
322 323
              }
            if ((j>0)&&(j<j2))
Martin Reinecke's avatar
Martin Reinecke committed
324
              dirty.v(i,j2) += (tmav(ix,jx2)*ws).real(); // upper left
Martin Reinecke's avatar
Martin Reinecke committed
325 326 327 328 329
            }
          }
        });
      }

Martin Reinecke's avatar
Martin Reinecke committed
330
    void grid2dirty(const mav<T,2> &grid,
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
331
      mav<T,2> &dirty) const
Martin Reinecke's avatar
Martin Reinecke committed
332 333
      {
      checkShape(grid.shape(), {nu,nv});
334
      mav<T,2> tmav({nu,nv});
Martin Reinecke's avatar
Martin Reinecke committed
335 336 337 338
      hartley2_2D<T>(grid, tmav, nthreads);
      grid2dirty_post(tmav, dirty);
      }

Martin Reinecke's avatar
Martin Reinecke committed
339
    void grid2dirty_c_overwrite_wscreen_add
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
340
      (mav<complex<T>,2> &grid, mav<T,2> &dirty, T w) const
Martin Reinecke's avatar
Martin Reinecke committed
341 342
      {
      checkShape(grid.shape(), {nu,nv});
Martin Reinecke's avatar
Martin Reinecke committed
343 344
      fmav<complex<T>> inout(grid);
      c2c(inout, inout, {0,1}, BACKWARD, T(1), nthreads);
Martin Reinecke's avatar
Martin Reinecke committed
345 346 347
      grid2dirty_post2(grid, dirty, w);
      }

Martin Reinecke's avatar
Martin Reinecke committed
348
    void dirty2grid_pre(const mav<T,2> &dirty,
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
349
      mav<T,2> &grid) const
Martin Reinecke's avatar
Martin Reinecke committed
350 351 352
      {
      checkShape(dirty.shape(), {nx_dirty, ny_dirty});
      checkShape(grid.shape(), {nu, nv});
Martin Reinecke's avatar
Martin Reinecke committed
353 354
      auto cfu = krn->corfunc(nx_dirty/2+1, 1./nu, nthreads);
      auto cfv = krn->corfunc(ny_dirty/2+1, 1./nv, nthreads);
Martin Reinecke's avatar
Martin Reinecke committed
355 356 357 358 359 360 361 362 363 364 365 366 367
      grid.fill(0);
      execStatic(nx_dirty, nthreads, 0, [&](Scheduler &sched)
        {
        while (auto rng=sched.getNext()) for(auto i=rng.lo; i<rng.hi; ++i)
          {
          int icfu = abs(int(nx_dirty/2)-int(i));
          for (size_t j=0; j<ny_dirty; ++j)
            {
            int icfv = abs(int(ny_dirty/2)-int(j));
            size_t i2 = nu-nx_dirty/2+i;
            if (i2>=nu) i2-=nu;
            size_t j2 = nv-ny_dirty/2+j;
            if (j2>=nv) j2-=nv;
Martin Reinecke's avatar
Martin Reinecke committed
368
            grid.v(i2,j2) = dirty(i,j)*T(cfu[icfu]*cfv[icfv]);
Martin Reinecke's avatar
Martin Reinecke committed
369 370 371 372
            }
          }
        });
      }
Martin Reinecke's avatar
Martin Reinecke committed
373
    void dirty2grid_pre2(const mav<T,2> &dirty,
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
374
      mav<complex<T>,2> &grid, T w) const
Martin Reinecke's avatar
Martin Reinecke committed
375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395
      {
      checkShape(dirty.shape(), {nx_dirty, ny_dirty});
      checkShape(grid.shape(), {nu, nv});
      grid.fill(0);

      double x0 = -0.5*nx_dirty*psx,
             y0 = -0.5*ny_dirty*psy;
      execStatic(nx_dirty/2+1, nthreads, 0, [&](Scheduler &sched)
        {
        while (auto rng=sched.getNext()) for(auto i=rng.lo; i<rng.hi; ++i)
          {
          T fx = T(x0+i*psx);
          fx *= fx;
          for (size_t j=0; j<=ny_dirty/2; ++j)
            {
            T fy = T(y0+j*psy);
            auto ws = wscreen(fx, fy*fy, w, false);
            size_t ix = nu-nx_dirty/2+i;
            if (ix>=nu) ix-=nu;
            size_t jx = nv-ny_dirty/2+j;
            if (jx>=nv) jx-=nv;
Martin Reinecke's avatar
Martin Reinecke committed
396
            grid.v(ix,jx) = dirty(i,j)*ws; // lower left
Martin Reinecke's avatar
Martin Reinecke committed
397 398 399 400 401 402 403
            size_t i2 = nx_dirty-i, j2 = ny_dirty-j;
            size_t ix2 = nu-nx_dirty/2+i2;
            if (ix2>=nu) ix2-=nu;
            size_t jx2 = nv-ny_dirty/2+j2;
            if (jx2>=nv) jx2-=nv;
            if ((i>0)&&(i<i2))
              {
Martin Reinecke's avatar
Martin Reinecke committed
404
              grid.v(ix2,jx) = dirty(i2,j)*ws; // lower right
Martin Reinecke's avatar
Martin Reinecke committed
405
              if ((j>0)&&(j<j2))
Martin Reinecke's avatar
Martin Reinecke committed
406
                grid.v(ix2,jx2) = dirty(i2,j2)*ws; // upper right
Martin Reinecke's avatar
Martin Reinecke committed
407 408
              }
            if ((j>0)&&(j<j2))
Martin Reinecke's avatar
Martin Reinecke committed
409
              grid.v(ix,jx2) = dirty(i,j2)*ws; // upper left
Martin Reinecke's avatar
Martin Reinecke committed
410 411 412 413 414
            }
          }
        });
      }

Martin Reinecke's avatar
Martin Reinecke committed
415
    void dirty2grid(const mav<T,2> &dirty,
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
416
      mav<T,2> &grid) const
Martin Reinecke's avatar
Martin Reinecke committed
417 418
      {
      dirty2grid_pre(dirty, grid);
Martin Reinecke's avatar
Martin Reinecke committed
419
      hartley2_2D<T>(grid, grid, nthreads);
Martin Reinecke's avatar
Martin Reinecke committed
420 421
      }

Martin Reinecke's avatar
Martin Reinecke committed
422
    void dirty2grid_c_wscreen(const mav<T,2> &dirty,
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
423
      mav<complex<T>,2> &grid, T w) const
Martin Reinecke's avatar
Martin Reinecke committed
424 425
      {
      dirty2grid_pre2(dirty, grid, w);
Martin Reinecke's avatar
Martin Reinecke committed
426 427
      fmav<complex<T>> inout(grid);
      c2c(inout, inout, {0,1}, FORWARD, T(1), nthreads);
Martin Reinecke's avatar
Martin Reinecke committed
428 429 430 431 432 433 434 435 436 437
      }

    void getpix(double u_in, double v_in, double &u, double &v, int &iu0, int &iv0) const
      {
      u=fmod1(u_in*psx)*nu;
      iu0 = min(int(u+ushift)-int(nu), maxiu0);
      v=fmod1(v_in*psy)*nv;
      iv0 = min(int(v+vshift)-int(nv), maxiv0);
      }

Martin Reinecke's avatar
Martin Reinecke committed
438
    void apply_wscreen(const mav<complex<T>,2> &dirty,
Martin Reinecke's avatar
Martin Reinecke committed
439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476
      mav<complex<T>,2> &dirty2, double w, bool adjoint) const
      {
      checkShape(dirty.shape(), {nx_dirty, ny_dirty});
      checkShape(dirty2.shape(), {nx_dirty, ny_dirty});

      double x0 = -0.5*nx_dirty*psx,
             y0 = -0.5*ny_dirty*psy;
      execStatic(nx_dirty/2+1, nthreads, 0, [&](Scheduler &sched)
        {
        while (auto rng=sched.getNext()) for(auto i=rng.lo; i<rng.hi; ++i)
          {
          T fx = T(x0+i*psx);
          fx *= fx;
          for (size_t j=0; j<=ny_dirty/2; ++j)
            {
            T fy = T(y0+j*psy);
            auto ws = wscreen(fx, fy*fy, T(w), adjoint);
            dirty2(i,j) = dirty(i,j)*ws; // lower left
            size_t i2 = nx_dirty-i, j2 = ny_dirty-j;
            if ((i>0)&&(i<i2))
              {
              dirty2(i2,j) = dirty(i2,j)*ws; // lower right
              if ((j>0)&&(j<j2))
                dirty2(i2,j2) = dirty(i2,j2)*ws; // upper right
              }
            if ((j>0)&&(j<j2))
              dirty2(i,j2) = dirty(i,j2)*ws; // upper left
            }
          }
        });
      }
  };

constexpr int logsquare=4;

template<typename T, typename T2=complex<T>> class Helper
  {
  private:
Martin Reinecke's avatar
Martin Reinecke committed
477
    const GridderConfig<T> &gconf;
Martin Reinecke's avatar
Martin Reinecke committed
478 479 480 481 482 483
    int nu, nv, nsafe, supp;
    const T2 *grid_r;
    T2 *grid_w;
    int su, sv;
    int iu0, iv0; // start index of the current visibility
    int bu0, bv0; // start index of the current buffer
Martin Reinecke's avatar
Martin Reinecke committed
484
    T wfac;
Martin Reinecke's avatar
Martin Reinecke committed
485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528

    vector<T2> rbuf, wbuf;
    bool do_w_gridding;
    double w0, xdw;
    vector<std::mutex> &locks;

    void dump() const
      {
      if (bu0<-nsafe) return; // nothing written into buffer yet

      int idxu = (bu0+nu)%nu;
      int idxv0 = (bv0+nv)%nv;
      for (int iu=0; iu<su; ++iu)
        {
        int idxv = idxv0;
        {
        std::lock_guard<std::mutex> lock(locks[idxu]);
        for (int iv=0; iv<sv; ++iv)
          {
          grid_w[idxu*nv + idxv] += wbuf[iu*sv + iv];
          if (++idxv>=nv) idxv=0;
          }
        }
        if (++idxu>=nu) idxu=0;
        }
      }

    void load()
      {
      int idxu = (bu0+nu)%nu;
      int idxv0 = (bv0+nv)%nv;
      for (int iu=0; iu<su; ++iu)
        {
        int idxv = idxv0;
        for (int iv=0; iv<sv; ++iv)
          {
          rbuf[iu*sv + iv] = grid_r[idxu*nv + idxv];
          if (++idxv>=nv) idxv=0;
          }
        if (++idxu>=nu) idxu=0;
        }
      }

  public:
Martin Reinecke's avatar
cleanup  
Martin Reinecke committed
529
    size_t nvec;
Martin Reinecke's avatar
Martin Reinecke committed
530 531 532
    const T2 *p0r;
    T2 *p0w;
    static constexpr size_t vlen=native_simd<T>::size();
Martin Reinecke's avatar
Martin Reinecke committed
533
    union kbuf {
Martin Reinecke's avatar
Martin Reinecke committed
534 535
      T scalar[64];
      native_simd<T> simd[64/vlen];
Martin Reinecke's avatar
Martin Reinecke committed
536
      };
Martin Reinecke's avatar
cleanup  
Martin Reinecke committed
537
    kbuf buf;
Martin Reinecke's avatar
Martin Reinecke committed
538

Martin Reinecke's avatar
Martin Reinecke committed
539
    Helper(const GridderConfig<T> &gconf_, const T2 *grid_r_, T2 *grid_w_,
Martin Reinecke's avatar
Martin Reinecke committed
540 541
      vector<std::mutex> &locks_, double w0_=-1, double dw_=-1)
      : gconf(gconf_), nu(gconf.Nu()), nv(gconf.Nv()), nsafe(gconf.Nsafe()),
Martin Reinecke's avatar
Martin Reinecke committed
542
        supp(gconf.Supp()), grid_r(grid_r_),
Martin Reinecke's avatar
Martin Reinecke committed
543 544 545 546 547 548 549
        grid_w(grid_w_), su(2*nsafe+(1<<logsquare)), sv(2*nsafe+(1<<logsquare)),
        bu0(-1000000), bv0(-1000000),
        rbuf(su*sv*(grid_r!=nullptr),T(0)),
        wbuf(su*sv*(grid_w!=nullptr),T(0)),
        do_w_gridding(dw_>0),
        w0(w0_),
        xdw(T(1)/dw_),
Martin Reinecke's avatar
cleanup  
Martin Reinecke committed
550 551
        locks(locks_),
        nvec((supp+vlen-1)/vlen)
Martin Reinecke's avatar
Martin Reinecke committed
552
      {
Martin Reinecke's avatar
cleanup  
Martin Reinecke committed
553
      MR_assert(supp<=32, "support too large");
Martin Reinecke's avatar
Martin Reinecke committed
554
      }
Martin Reinecke's avatar
Martin Reinecke committed
555 556 557
    ~Helper() { if (grid_w) dump(); }

    int lineJump() const { return sv; }
Martin Reinecke's avatar
Martin Reinecke committed
558
    T Wfac() const { return wfac; }
Martin Reinecke's avatar
Martin Reinecke committed
559 560
    void prep(const UVW &in)
      {
Martin Reinecke's avatar
Martin Reinecke committed
561
      const auto &krn(*(gconf.krn));
Martin Reinecke's avatar
Martin Reinecke committed
562 563 564 565 566
      double u, v;
      gconf.getpix(in.u, in.v, u, v, iu0, iv0);
      double xsupp=2./supp;
      double x0 = xsupp*(iu0-u);
      double y0 = xsupp*(iv0-v);
Martin Reinecke's avatar
cleanup  
Martin Reinecke committed
567 568
      krn.eval(T(x0), &buf.simd[0]);
      krn.eval(T(y0), &buf.simd[nvec]);
Martin Reinecke's avatar
Martin Reinecke committed
569
      if (do_w_gridding)
Martin Reinecke's avatar
Martin Reinecke committed
570
        wfac = krn.eval_single(T(xdw*xsupp*abs(w0-in.w)));
Martin Reinecke's avatar
Martin Reinecke committed
571 572 573 574 575 576 577 578 579 580 581 582 583 584 585
      if ((iu0<bu0) || (iv0<bv0) || (iu0+supp>bu0+su) || (iv0+supp>bv0+sv))
        {
        if (grid_w) { dump(); fill(wbuf.begin(), wbuf.end(), T(0)); }
        bu0=((((iu0+nsafe)>>logsquare)<<logsquare))-nsafe;
        bv0=((((iv0+nsafe)>>logsquare)<<logsquare))-nsafe;
        if (grid_r) load();
        }
      p0r = grid_r ? rbuf.data() + sv*(iu0-bu0) + iv0-bv0 : nullptr;
      p0w = grid_w ? wbuf.data() + sv*(iu0-bu0) + iv0-bv0 : nullptr;
      }
  };

template<class T, class Serv> class SubServ
  {
  private:
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
586 587
    Serv &srv;
    mav<idx_t,1> subidx;
Martin Reinecke's avatar
Martin Reinecke committed
588 589

  public:
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
590
    SubServ(Serv &orig, const mav<idx_t,1> &subidx_)
Martin Reinecke's avatar
Martin Reinecke committed
591 592 593 594
      : srv(orig), subidx(subidx_){}
    size_t Nvis() const { return subidx.size(); }
    const Baselines &getBaselines() const { return srv.getBaselines(); }
    UVW getCoord(size_t i) const
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
595
      { return srv.getCoord(subidx(i)); }
Martin Reinecke's avatar
Martin Reinecke committed
596
    complex<T> getVis(size_t i) const
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
597 598 599 600 601 602
      { return srv.getVis(subidx(i)); }
    idx_t getIdx(size_t i) const { return srv.getIdx(subidx(i)); }
    void setVis (size_t i, const complex<T> &v)
      { srv.setVis(subidx(i), v); }
    void addVis (size_t i, const complex<T> &v)
      { srv.addVis(subidx(i), v); }
Martin Reinecke's avatar
Martin Reinecke committed
603 604 605 606 607 608
  };

template<class T, class T2> class MsServ
  {
  private:
    const Baselines &baselines;
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
609
    mav<idx_t,1> idx;
Martin Reinecke's avatar
Martin Reinecke committed
610
    T2 ms;
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
611
    mav<T,2> wgt;
Martin Reinecke's avatar
Martin Reinecke committed
612 613 614 615 616 617 618
    size_t nvis;
    bool have_wgt;

  public:
    using Tsub = SubServ<T, MsServ>;

    MsServ(const Baselines &baselines_,
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
619
    const mav<idx_t,1> &idx_, T2 ms_, const mav<T,2> &wgt_)
Martin Reinecke's avatar
Martin Reinecke committed
620 621 622 623 624 625
      : baselines(baselines_), idx(idx_), ms(ms_), wgt(wgt_),
        nvis(idx.shape(0)), have_wgt(wgt.size()!=0)
      {
      checkShape(ms.shape(), {baselines.Nrows(), baselines.Nchannels()});
      if (have_wgt) checkShape(wgt.shape(), ms.shape());
      }
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
626
    Tsub getSubserv(const mav<idx_t,1> &subidx)
Martin Reinecke's avatar
Martin Reinecke committed
627 628 629 630 631 632 633 634 635 636 637
      { return Tsub(*this, subidx); }
    size_t Nvis() const { return nvis; }
    const Baselines &getBaselines() const { return baselines; }
    UVW getCoord(size_t i) const
      { return baselines.effectiveCoord(idx(i)); }
    complex<T> getVis(size_t i) const
      {
      auto rc = baselines.getRowChan(idx(i));
      return have_wgt ? ms(rc.row, rc.chan)*wgt(rc.row, rc.chan)
                      : ms(rc.row, rc.chan);
      }
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
638 639
    idx_t getIdx(size_t i) const { return idx(i); }
    void setVis (size_t i, const complex<T> &v)
Martin Reinecke's avatar
Martin Reinecke committed
640 641
      {
      auto rc = baselines.getRowChan(idx(i));
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
642
      ms.w()(rc.row, rc.chan) = have_wgt ? v*wgt(rc.row, rc.chan) : v;
Martin Reinecke's avatar
Martin Reinecke committed
643
      }
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
644
    void addVis (size_t i, const complex<T> &v)
Martin Reinecke's avatar
Martin Reinecke committed
645 646
      {
      auto rc = baselines.getRowChan(idx(i));
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
647
      ms.v(rc.row, rc.chan) += have_wgt ? v*wgt(rc.row, rc.chan) : v;
Martin Reinecke's avatar
Martin Reinecke committed
648 649 650 651
      }
  };
template<class T, class T2> MsServ<T, T2> makeMsServ
  (const Baselines &baselines,
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
652
   const mav<idx_t,1> &idx, T2 &ms, const mav<T,2> &wgt)
Martin Reinecke's avatar
Martin Reinecke committed
653 654 655
  { return MsServ<T, T2>(baselines, idx, ms, wgt); }

template<typename T, typename Serv> void x2grid_c
Martin Reinecke's avatar
Martin Reinecke committed
656
  (const GridderConfig<T> &gconf, Serv &srv, mav<complex<T>,2> &grid,
Martin Reinecke's avatar
Martin Reinecke committed
657 658 659 660 661 662 663 664 665 666 667 668
  double w0=-1, double dw=-1)
  {
  checkShape(grid.shape(), {gconf.Nu(), gconf.Nv()});
  MR_assert(grid.contiguous(), "grid is not contiguous");
  size_t supp = gconf.Supp();
  size_t nthreads = gconf.Nthreads();
  bool do_w_gridding = dw>0;
  vector<std::mutex> locks(gconf.Nu());

  size_t np = srv.Nvis();
  execGuided(np, nthreads, 100, 0.2, [&](Scheduler &sched)
    {
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
669
    Helper<T> hlp(gconf, nullptr, grid.vdata(), locks, w0, dw);
Martin Reinecke's avatar
Martin Reinecke committed
670
    int jump = hlp.lineJump();
Martin Reinecke's avatar
cleanup  
Martin Reinecke committed
671 672
    const T * DUCC0_RESTRICT ku = hlp.buf.scalar;
    const T * DUCC0_RESTRICT kv = hlp.buf.scalar+hlp.vlen*hlp.nvec;
Martin Reinecke's avatar
Martin Reinecke committed
673 674 675 676 677 678

    while (auto rng=sched.getNext()) for(auto ipart=rng.lo; ipart<rng.hi; ++ipart)
      {
      UVW coord = srv.getCoord(ipart);
      auto flip = coord.FixW();
      hlp.prep(coord);
Martin Reinecke's avatar
Martin Reinecke committed
679
      auto * DUCC0_RESTRICT ptr = hlp.p0w;
Martin Reinecke's avatar
Martin Reinecke committed
680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702
      auto v(srv.getVis(ipart));
      if (do_w_gridding) v*=hlp.Wfac();
      if (flip) v=conj(v);
      for (size_t cu=0; cu<supp; ++cu)
        {
        complex<T> tmp(v*ku[cu]);
        size_t cv=0;
        for (; cv+3<supp; cv+=4)
          {
          ptr[cv  ] += tmp*kv[cv  ];
          ptr[cv+1] += tmp*kv[cv+1];
          ptr[cv+2] += tmp*kv[cv+2];
          ptr[cv+3] += tmp*kv[cv+3];
          }
        for (; cv<supp; ++cv)
          ptr[cv] += tmp*kv[cv];
        ptr+=jump;
        }
      }
    });
  }

template<typename T, typename Serv> void grid2x_c
Martin Reinecke's avatar
Martin Reinecke committed
703
  (const GridderConfig<T> &gconf, const mav<complex<T>,2> &grid,
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
704
  Serv &srv, double w0=-1, double dw=-1)
Martin Reinecke's avatar
Martin Reinecke committed
705 706 707 708 709 710 711 712 713 714 715 716 717 718
  {
  checkShape(grid.shape(), {gconf.Nu(), gconf.Nv()});
  MR_assert(grid.contiguous(), "grid is not contiguous");
  size_t supp = gconf.Supp();
  size_t nthreads = gconf.Nthreads();
  bool do_w_gridding = dw>0;
  vector<std::mutex> locks(gconf.Nu());

  // Loop over sampling points
  size_t np = srv.Nvis();
  execGuided(np, nthreads, 1000, 0.5, [&](Scheduler &sched)
    {
    Helper<T> hlp(gconf, grid.data(), nullptr, locks, w0, dw);
    int jump = hlp.lineJump();
Martin Reinecke's avatar
cleanup  
Martin Reinecke committed
719 720
    const T * DUCC0_RESTRICT ku = hlp.buf.scalar;
    const T * DUCC0_RESTRICT kv = hlp.buf.scalar+hlp.vlen*hlp.nvec;
Martin Reinecke's avatar
Martin Reinecke committed
721 722 723 724 725 726 727

    while (auto rng=sched.getNext()) for(auto ipart=rng.lo; ipart<rng.hi; ++ipart)
      {
      UVW coord = srv.getCoord(ipart);
      auto flip = coord.FixW();
      hlp.prep(coord);
      complex<T> r = 0;
Martin Reinecke's avatar
Martin Reinecke committed
728
      const auto * DUCC0_RESTRICT ptr = hlp.p0r;
Martin Reinecke's avatar
Martin Reinecke committed
729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749
      for (size_t cu=0; cu<supp; ++cu)
        {
        complex<T> tmp(0);
        size_t cv=0;
        for (; cv+3<supp; cv+=4)
          tmp += ptr[cv  ]*kv[cv  ]
               + ptr[cv+1]*kv[cv+1]
               + ptr[cv+2]*kv[cv+2]
               + ptr[cv+3]*kv[cv+3];
        for (; cv<supp; ++cv)
          tmp += ptr[cv] * kv[cv];
        r += tmp*ku[cu];
        ptr += jump;
        }
      if (flip) r=conj(r);
      if (do_w_gridding) r*=hlp.Wfac();
      srv.addVis(ipart, r);
      }
    });
  }

Martin Reinecke's avatar
Martin Reinecke committed
750 751
template<typename T> void apply_global_corrections(const GridderConfig<T> &gconf,
  mav<T,2> &dirty, double dw, bool divide_by_n)
Martin Reinecke's avatar
Martin Reinecke committed
752 753 754 755 756 757 758 759
  {
  auto nx_dirty=gconf.Nxdirty();
  auto ny_dirty=gconf.Nydirty();
  size_t nthreads = gconf.Nthreads();
  auto psx=gconf.Pixsize_x();
  auto psy=gconf.Pixsize_y();
  double x0 = -0.5*nx_dirty*psx,
         y0 = -0.5*ny_dirty*psy;
Martin Reinecke's avatar
Martin Reinecke committed
760 761
  auto cfu = gconf.krn->corfunc(nx_dirty/2+1, 1./gconf.Nu(), nthreads);
  auto cfv = gconf.krn->corfunc(ny_dirty/2+1, 1./gconf.Nv(), nthreads);
Martin Reinecke's avatar
Martin Reinecke committed
762 763 764 765 766 767 768 769 770 771 772 773 774 775 776
  execStatic(nx_dirty/2+1, nthreads, 0, [&](Scheduler &sched)
    {
    while (auto rng=sched.getNext()) for(auto i=rng.lo; i<rng.hi; ++i)
      {
      auto fx = T(x0+i*psx);
      fx *= fx;
      for (size_t j=0; j<=ny_dirty/2; ++j)
        {
        auto fy = T(y0+j*psy);
        fy*=fy;
        T fct = 0;
        auto tmp = 1-fx-fy;
        if (tmp>=0)
          {
          auto nm1 = (-fx-fy)/(sqrt(tmp)+1); // accurate form of sqrt(1-x-y)-1
Martin Reinecke's avatar
Martin Reinecke committed
777
          fct = T(gconf.krn->corfunc(nm1*dw));
Martin Reinecke's avatar
Martin Reinecke committed
778 779 780 781 782 783 784 785 786 787
          if (divide_by_n)
            fct /= nm1+1;
          }
        else // beyond the horizon, don't really know what to do here
          {
          if (divide_by_n)
            fct=0;
          else
            {
            auto nm1 = sqrt(-tmp)-1;
Martin Reinecke's avatar
Martin Reinecke committed
788
            fct = T(gconf.krn->corfunc(nm1*dw));
Martin Reinecke's avatar
Martin Reinecke committed
789 790 791 792
            }
          }
        fct *= T(cfu[nx_dirty/2-i]*cfv[ny_dirty/2-j]);
        size_t i2 = nx_dirty-i, j2 = ny_dirty-j;
Martin Reinecke's avatar
Martin Reinecke committed
793
        dirty.v(i,j)*=fct;
Martin Reinecke's avatar
Martin Reinecke committed
794 795
        if ((i>0)&&(i<i2))
          {
Martin Reinecke's avatar
Martin Reinecke committed
796
          dirty.v(i2,j)*=fct;
Martin Reinecke's avatar
Martin Reinecke committed
797
          if ((j>0)&&(j<j2))
Martin Reinecke's avatar
Martin Reinecke committed
798
            dirty.v(i2,j2)*=fct;
Martin Reinecke's avatar
Martin Reinecke committed
799 800
          }
        if ((j>0)&&(j<j2))
Martin Reinecke's avatar
Martin Reinecke committed
801
          dirty.v(i,j2)*=fct;
Martin Reinecke's avatar
Martin Reinecke committed
802 803 804 805 806
        }
      }
    });
  }

Martin Reinecke's avatar
Martin Reinecke committed
807
template<typename T, typename Serv> class WgridHelper
Martin Reinecke's avatar
Martin Reinecke committed
808 809
  {
  private:
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
810
    Serv &srv;
Martin Reinecke's avatar
Martin Reinecke committed
811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833
    double wmin, dw;
    size_t nplanes, supp;
    vector<vector<idx_t>> minplane;
    size_t verbosity;

    int curplane;
    vector<idx_t> subidx;

    static void wminmax(const Serv &srv, double &wmin, double &wmax)
      {
      size_t nvis = srv.Nvis();

      wmin= 1e38;
      wmax=-1e38;
      // FIXME maybe this can be done more intelligently
      for (size_t ipart=0; ipart<nvis; ++ipart)
        {
        auto wval = abs(srv.getCoord(ipart).w);
        wmin = min(wmin,wval);
        wmax = max(wmax,wval);
        }
      }

Martin Reinecke's avatar
Martin Reinecke committed
834 835
    template<typename T2> static void update_idx(vector<T2> &v, const vector<T2> &add,
      const vector<T2> &del)
Martin Reinecke's avatar
Martin Reinecke committed
836 837
      {
      MR_assert(v.size()>=del.size(), "must not happen");
Martin Reinecke's avatar
Martin Reinecke committed
838
      vector<T2> res;
Martin Reinecke's avatar
Martin Reinecke committed
839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860
      res.reserve((v.size()+add.size())-del.size());
      auto iin=v.begin(), ein=v.end();
      auto iadd=add.begin(), eadd=add.end();
      auto irem=del.begin(), erem=del.end();

      while(iin!=ein)
        {
        if ((irem!=erem) && (*iin==*irem))
          {  ++irem; ++iin; } // skip removed entry
        else if ((iadd!=eadd) && (*iadd<*iin))
           res.push_back(*(iadd++)); // add new entry
        else
          res.push_back(*(iin++));
        }
      MR_assert(irem==erem, "must not happen");
      while(iadd!=eadd)
        res.push_back(*(iadd++));
      MR_assert(res.size()==(v.size()+add.size())-del.size(), "must not happen");
      v.swap(res);
      }

  public:
Martin Reinecke's avatar
Martin Reinecke committed
861
    WgridHelper(const GridderConfig<T> &gconf, Serv &srv_, size_t verbosity_)
Martin Reinecke's avatar
Martin Reinecke committed
862
      : srv(srv_), supp(gconf.Supp()), verbosity(verbosity_), curplane(-1)
Martin Reinecke's avatar
Martin Reinecke committed
863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878
      {
      size_t nvis = srv.Nvis();
      size_t nthreads = gconf.Nthreads();
      double wmax;

      wminmax(srv, wmin, wmax);
      if (verbosity>0) cout << "Using " << nthreads << " thread"
                            << ((nthreads!=1) ? "s" : "") << endl;
      if (verbosity>0) cout << "W range: " << wmin << " to " << wmax << endl;

      double x0 = -0.5*gconf.Nxdirty()*gconf.Pixsize_x(),
             y0 = -0.5*gconf.Nydirty()*gconf.Pixsize_y();
      double nmin = sqrt(max(1.-x0*x0-y0*y0,0.))-1.;
      if (x0*x0+y0*y0>1.)
        nmin = -sqrt(abs(1.-x0*x0-y0*y0))-1.;
      dw = 0.25/abs(nmin);
Martin Reinecke's avatar
Martin Reinecke committed
879
      nplanes = size_t((wmax-wmin)/dw+supp);
Martin Reinecke's avatar
Martin Reinecke committed
880
      wmin = (wmin+wmax)*0.5 - 0.5*(nplanes-1)*dw;
Martin Reinecke's avatar
Martin Reinecke committed
881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914
      if (verbosity>0) cout << "Kernel support: " << supp << endl;
      if (verbosity>0) cout << "nplanes: " << nplanes << endl;

      minplane.resize(nplanes);
#if 0
      // extra short, but potentially inefficient version:
      for (size_t ipart=0; ipart<nvis; ++ipart)
        {
        int plane0 = max(0,int(1+(abs(srv.getCoord(ipart).w)-(0.5*supp*dw)-wmin)/dw));
        minplane[plane0].push_back(idx_t(ipart));
        }
#else
      // more efficient: precalculate final vector sizes and avoid reallocations
      vector<size_t> cnt(nplanes,0);
      for(size_t ipart=0; ipart<nvis; ++ipart)
        {
        int plane0 = max(0,int(1+(abs(srv.getCoord(ipart).w)-(0.5*supp*dw)-wmin)/dw));
        ++cnt[plane0];
        }

      // fill minplane
      for (size_t j=0; j<nplanes; ++j)
        minplane[j].resize(cnt[j]);
      vector<size_t> ofs(nplanes, 0);
      for (size_t ipart=0; ipart<nvis; ++ipart)
        {
        int plane0 = max(0,int(1+(abs(srv.getCoord(ipart).w)-(0.5*supp*dw)-wmin)/dw));
        minplane[plane0][ofs[plane0]++]=idx_t(ipart);
        }
#endif
      }

    typename Serv::Tsub getSubserv() const
      {
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
915
      auto subidx2 = mav<idx_t, 1>(subidx.data(), {subidx.size()});
Martin Reinecke's avatar
Martin Reinecke committed
916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932
      return srv.getSubserv(subidx2);
      }
    double W() const { return wmin+curplane*dw; }
    size_t Nvis() const { return subidx.size(); }
    double DW() const { return dw; }
    bool advance()
      {
      if (++curplane>=int(nplanes)) return false;
      update_idx(subidx, minplane[curplane], curplane>=int(supp) ? minplane[curplane-supp] : vector<idx_t>());
      if (verbosity>1)
        cout << "Working on plane " << curplane << " containing " << subidx.size()
             << " visibilities" << endl;
      return true;
      }
  };

template<typename T, typename Serv> void x2dirty(
Martin Reinecke's avatar
Martin Reinecke committed
933
  const GridderConfig<T> &gconf, Serv &srv, mav<T,2> &dirty,
Martin Reinecke's avatar
Martin Reinecke committed
934 935 936 937 938
  bool do_wstacking, size_t verbosity)
  {
  if (do_wstacking)
    {
    if (verbosity>0) cout << "Gridding using improved w-stacking" << endl;
Martin Reinecke's avatar
Martin Reinecke committed
939
    WgridHelper<T, Serv> hlp(gconf, srv, verbosity);
Martin Reinecke's avatar
Martin Reinecke committed
940 941
    double dw = hlp.DW();
    dirty.fill(0);
942
    mav<complex<T>,2> grid({gconf.Nu(),gconf.Nv()});
Martin Reinecke's avatar
Martin Reinecke committed
943 944 945 946
    while(hlp.advance())  // iterate over w planes
      {
      if (hlp.Nvis()==0) continue;
      grid.fill(0);
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
947 948
      auto serv = hlp.getSubserv();
      x2grid_c(gconf, serv, grid, hlp.W(), dw);
Martin Reinecke's avatar
Martin Reinecke committed
949 950 951
      gconf.grid2dirty_c_overwrite_wscreen_add(grid, dirty, T(hlp.W()));
      }
    // correct for w gridding etc.
Martin Reinecke's avatar
Martin Reinecke committed
952
    apply_global_corrections(gconf, dirty, dw, true);
Martin Reinecke's avatar
Martin Reinecke committed
953 954 955 956 957 958 959 960
    }
  else
    {
    if (verbosity>0)
      cout << "Gridding without w-stacking: " << srv.Nvis()
           << " visibilities" << endl;
    if (verbosity>0) cout << "Using " << gconf.Nthreads() << " threads" << endl;

961 962
    mav<complex<T>,2> grid({gconf.Nu(), gconf.Nv()});
    grid.fill(0.);
Martin Reinecke's avatar
Martin Reinecke committed
963
    x2grid_c(gconf, srv, grid);
964
    mav<T,2> rgrid(grid.shape());
Martin Reinecke's avatar
Martin Reinecke committed
965 966
    complex2hartley(grid, rgrid, gconf.Nthreads());
    gconf.grid2dirty(rgrid, dirty);
Martin Reinecke's avatar
Martin Reinecke committed
967 968 969 970
    }
  }

template<typename T, typename Serv> void dirty2x(
Martin Reinecke's avatar
Martin Reinecke committed
971
  const GridderConfig<T> &gconf,  const mav<T,2> &dirty,
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
972
  Serv &srv, bool do_wstacking, size_t verbosity)
Martin Reinecke's avatar
Martin Reinecke committed
973 974 975 976 977
  {
  if (do_wstacking)
    {
    size_t nx_dirty=gconf.Nxdirty(), ny_dirty=gconf.Nydirty();
    if (verbosity>0) cout << "Degridding using improved w-stacking" << endl;
Martin Reinecke's avatar
Martin Reinecke committed
978
    WgridHelper<T, Serv> hlp(gconf, srv, verbosity);
Martin Reinecke's avatar
Martin Reinecke committed
979
    double dw = hlp.DW();
980
    mav<T,2> tdirty({nx_dirty,ny_dirty});
Martin Reinecke's avatar
Martin Reinecke committed
981 982
    for (size_t i=0; i<nx_dirty; ++i)
      for (size_t j=0; j<ny_dirty; ++j)
Martin Reinecke's avatar
Martin Reinecke committed
983
        tdirty.v(i,j) = dirty(i,j);
Martin Reinecke's avatar
Martin Reinecke committed
984
    // correct for w gridding etc.
Martin Reinecke's avatar
Martin Reinecke committed
985
    apply_global_corrections(gconf, tdirty, dw, true);
986
    mav<complex<T>,2> grid({gconf.Nu(),gconf.Nv()});
Martin Reinecke's avatar
Martin Reinecke committed
987 988 989
    while(hlp.advance())  // iterate over w planes
      {
      if (hlp.Nvis()==0) continue;
Martin Reinecke's avatar
Martin Reinecke committed
990
      gconf.dirty2grid_c_wscreen(tdirty, grid, T(hlp.W()));
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
991 992
      auto serv = hlp.getSubserv();
      grid2x_c(gconf, grid, serv, hlp.W(), dw);
Martin Reinecke's avatar
Martin Reinecke committed
993 994 995 996 997 998 999 1000 1001
      }
    }
  else
    {
    if (verbosity>0)
      cout << "Degridding without w-stacking: " << srv.Nvis()
           << " visibilities" << endl;
    if (verbosity>0) cout << "Using " << gconf.Nthreads() << " threads" << endl;

1002
    mav<T,2> grid({gconf.Nu(), gconf.Nv()});
Martin Reinecke's avatar
Martin Reinecke committed
1003
    gconf.dirty2grid(dirty, grid);
1004
    mav<complex<T>,2> grid2(grid.shape());
Martin Reinecke's avatar
Martin Reinecke committed
1005 1006
    hartley2complex(grid, grid2, gconf.Nthreads());
    grid2x_c(gconf, grid2, srv);
Martin Reinecke's avatar
Martin Reinecke committed
1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020
    }
  }

void calc_share(size_t nshares, size_t myshare, size_t nwork, size_t &lo,
  size_t &hi)
  {
  size_t nbase = nwork/nshares;
  size_t additional = nwork%nshares;
  lo = myshare*nbase + ((myshare<additional) ? myshare : additional);
  hi = lo+nbase+(myshare<additional);
  }


template<typename T> vector<idx_t> getWgtIndices(const Baselines &baselines,
Martin Reinecke's avatar
Martin Reinecke committed
1021
  const GridderConfig<T> &gconf, const mav<T,2> &wgt,
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
1022
  const mav<complex<T>,2> &ms)
Martin Reinecke's avatar
Martin Reinecke committed
1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038
  {
  size_t nrow=baselines.Nrows(),
         nchan=baselines.Nchannels(),
         nsafe=gconf.Nsafe();
  bool have_wgt=wgt.size()!=0;
  if (have_wgt) checkShape(wgt.shape(),{nrow,nchan});
  bool have_ms=ms.size()!=0;
  if (have_ms) checkShape(ms.shape(), {nrow,nchan});
  constexpr int side=1<<logsquare;
  size_t nbu = (gconf.Nu()+1+side-1) >> logsquare,
         nbv = (gconf.Nv()+1+side-1) >> logsquare;
  vector<idx_t> acc(nbu*nbv+1,0);
  vector<idx_t> tmp(nrow*nchan);

  for (idx_t irow=0, idx=0; irow<nrow; ++irow)
    for (idx_t ichan=0; ichan<nchan; ++ichan, ++idx)
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
1039
      if (((!have_ms ) || (norm(ms(irow,ichan))!=0)) &&
Martin Reinecke's avatar
Martin Reinecke committed
1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065
          ((!have_wgt) || (wgt(irow,ichan)!=0)))
        {
        auto uvw = baselines.effectiveCoord(RowChan{irow,idx_t(ichan)});
        if (uvw.w<0) uvw.Flip();
        double u, v;
        int iu0, iv0;
        gconf.getpix(uvw.u, uvw.v, u, v, iu0, iv0);
        iu0 = (iu0+nsafe)>>logsquare;
        iv0 = (iv0+nsafe)>>logsquare;
        ++acc[nbv*iu0 + iv0 + 1];
        tmp[idx] = nbv*iu0 + iv0;
        }
      else
        tmp[idx] = ~idx_t(0);

  for (size_t i=1; i<acc.size(); ++i)
    acc[i] += acc[i-1];

  vector<idx_t> res(acc.back());
  for (size_t irow=0, idx=0; irow<nrow; ++irow)
    for (size_t ichan=0; ichan<nchan; ++ichan, ++idx)
      if (tmp[idx]!=(~idx_t(0)))
        res[acc[tmp[idx]]++] = baselines.getIdx(irow, ichan);
  return res;
  }

1066
template<typename T> void ms2dirty(const mav<double,2> &uvw,
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
1067 1068 1069
  const mav<double,1> &freq, const mav<complex<T>,2> &ms,
  const mav<T,2> &wgt, double pixsize_x, double pixsize_y, size_t nu, size_t nv, double epsilon,
  bool do_wstacking, size_t nthreads, mav<T,2> &dirty, size_t verbosity,
Martin Reinecke's avatar
Martin Reinecke committed
1070 1071 1072
  bool negate_v=false)
  {
  Baselines baselines(uvw, freq, negate_v);
1073 1074
  // adjust for increased error when gridding in 2 or 3 dimensions
  epsilon /= do_wstacking ? 3 : 2;
Martin Reinecke's avatar
Martin Reinecke committed
1075
  GridderConfig<T> gconf(dirty.shape(0), dirty.shape(1), nu, nv, epsilon, pixsize_x, pixsize_y, nthreads);
Martin Reinecke's avatar
Martin Reinecke committed
1076
  auto idx = getWgtIndices(baselines, gconf, wgt, ms);
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
1077 1078 1079
  auto idx2 = mav<idx_t,1>(idx.data(),{idx.size()});
  auto serv = makeMsServ(baselines,idx2,ms,wgt);
  x2dirty(gconf, serv, dirty, do_wstacking, verbosity);
Martin Reinecke's avatar
Martin Reinecke committed
1080 1081
  }

1082
template<typename T> void dirty2ms(const mav<double,2> &uvw,
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
1083 1084 1085
  const mav<double,1> &freq, const mav<T,2> &dirty,
  const mav<T,2> &wgt, double pixsize_x, double pixsize_y, size_t nu, size_t nv,double epsilon,
  bool do_wstacking, size_t nthreads, mav<complex<T>,2> &ms,
Martin Reinecke's avatar
Martin Reinecke committed
1086 1087 1088
  size_t verbosity, bool negate_v=false)
  {
  Baselines baselines(uvw, freq, negate_v);
1089 1090
  // adjust for increased error when gridding in 2 or 3 dimensions
  epsilon /= do_wstacking ? 3 : 2;
Martin Reinecke's avatar
Martin Reinecke committed
1091
  GridderConfig<T> gconf(dirty.shape(0), dirty.shape(1), nu, nv, epsilon, pixsize_x, pixsize_y, nthreads);
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
1092
  mav<complex<T>,2> null_ms(nullptr, {0,0}, true);
Martin Reinecke's avatar
Martin Reinecke committed
1093
  auto idx = getWgtIndices(baselines, gconf, wgt, null_ms);
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
1094
  auto idx2 = mav<idx_t,1>(idx.data(),{idx.size()});
Martin Reinecke's avatar
Martin Reinecke committed
1095
  ms.fill(0);
Martin Reinecke's avatar
stage 2  
Martin Reinecke committed
1096 1097
  auto serv = makeMsServ(baselines,idx2,ms,wgt);
  dirty2x(gconf, dirty, serv, do_wstacking, verbosity);
Martin Reinecke's avatar
Martin Reinecke committed
1098 1099
  }

Martin Reinecke's avatar
Martin Reinecke committed
1100
} // namespace detail_gridder
Martin Reinecke's avatar
Martin Reinecke committed
1101 1102

// public names
Martin Reinecke's avatar
Martin Reinecke committed
1103 1104 1105
using detail_gridder::ms2dirty;
using detail_gridder::dirty2ms;

Martin Reinecke's avatar
Martin Reinecke committed
1106
} // namespace ducc0
Martin Reinecke's avatar
Martin Reinecke committed
1107 1108

#endif