function [] = convert_fluid_hdf2ucf(fhdf,fucf,fproc)
    % [] = convert_particles_hdf2ucf(fhdf,fucf)
    % Converts a H5Part file containing particle data to a file in UCF format.
    % Input
    %   fhdf          file path to HDF file (input file)
    %   fucf          file path to UCF file (output file)

    % Get basename for UCF chunks
    [fdir,fbase] = fileparts(fucf);
    fbasepath = fullfile(fdir,fbase);
        
    % Loop through timesteps
    fprintf('[HDF read]  %s\n',fhdf);
    
    % Read target proc grid from file
    [ibegu,iendu,jbegu,jendu,kbegu,kendu,...
     ibegv,iendv,jbegv,jendv,kbegv,kendv,...
     ibegw,iendw,jbegw,jendw,kbegw,kendw,...
     ibegp,iendp,jbegp,jendp,kbegp,kendp] = read_procgrid_ucf(fproc);
    nxprocs = numel(ibegu);
    nyprocs = numel(jbegu);
    nzprocs = numel(kbegu);
    nprocs = nxprocs*nyprocs*nzprocs;

    % Open HDF
    id_hdf = H5F.open(fhdf,'H5F_ACC_RDONLY','H5P_DEFAULT');
    
    % Read simulation time from HDF and create UCF timestep
    id_dset = H5D.open(id_hdf,'Time');
    time = H5D.read(id_dset);
    H5D.close(id_dset);
    
    % Read periodicity for reconstruction of ghost cells
    id_group = H5G.open(id_hdf,'/Domain');
    id_dset = H5D.open(id_group,'PeriodicityX'); x_periodic = H5D.read(id_dset); H5D.close(id_dset);
    id_dset = H5D.open(id_group,'PeriodicityY'); y_periodic = H5D.read(id_dset); H5D.close(id_dset);
    id_dset = H5D.open(id_group,'PeriodicityZ'); z_periodic = H5D.read(id_dset); H5D.close(id_dset);
    H5G.close(id_group);

    % Read full fields from HDF
    id_group = H5G.open(id_hdf,'/Fluid');
    id_dset = H5D.open(id_group,'VelocityX'); u = H5D.read(id_dset); H5D.close(id_dset);
    id_dset = H5D.open(id_group,'VelocityY'); v = H5D.read(id_dset); H5D.close(id_dset);
    id_dset = H5D.open(id_group,'VelocityZ'); w = H5D.read(id_dset); H5D.close(id_dset);
    id_dset = H5D.open(id_group,'Pressure');  p = H5D.read(id_dset); H5D.close(id_dset);
    H5G.close(id_group);
    
    % Close HDF
    H5F.close(id_hdf);
    clear id_hdf    

    % Determine global dimensions
    nxu = size(u,1); nxv = size(v,1); nxw = size(w,1); nxp = size(p,1);
    nyu = size(u,2); nyv = size(v,2); nyw = size(w,2); nyp = size(p,2);
    nzu = size(u,3); nzv = size(v,3); nzw = size(w,3); nzp = size(p,3);

    if nxp~=iendp(end) || nyp~=jendp(end) || nzp~=kendp(end)
      error('Processor grid does not match data. %d,%d,%d <-> %d,%d,%d',nxp,nyp,nzp,iendp(end),jendp(end),kendp(end));
    end

    for ixproc=0:nxprocs-1
      for iyproc=0:nyprocs-1
        for izproc=0:nzprocs-1
          [iproc] = locfun_proc_id(ixproc,iyproc,izproc,nxprocs,nyprocs,nzprocs);
          fname = sprintf('%s.%05d',fbasepath,iproc);
          fprintf('[UCF write] %s (out of %d)\n',fname,nprocs);
          
          obj = ucf(fname,'create');
          obj.setFileHeader('field','rank',[iproc,ixproc,iyproc,izproc],'endian','a');
          obj.appendStep(time);
          
          % Get processor bounadries for this file
          ibu = ibegu(ixproc+1); ieu = iendu(ixproc+1); 
          jbu = jbegu(iyproc+1); jeu = jendu(iyproc+1); 
          kbu = kbegu(izproc+1); keu = kendu(izproc+1);
          
          ibv = ibegv(ixproc+1); iev = iendv(ixproc+1); 
          jbv = jbegv(iyproc+1); jev = jendv(iyproc+1); 
          kbv = kbegv(izproc+1); kev = kendv(izproc+1); 
          
          ibw = ibegw(ixproc+1); iew = iendw(ixproc+1); 
          jbw = jbegw(iyproc+1); jew = jendw(iyproc+1); 
          kbw = kbegw(izproc+1); kew = kendw(izproc+1); 
          
          ibp = ibegp(ixproc+1); iep = iendp(ixproc+1);
          jbp = jbegp(iyproc+1); jep = jendp(iyproc+1);
          kbp = kbegp(izproc+1); kep = kendp(izproc+1);
          
          % Determine local grid size
          nxul = ieu-ibu+1; nxvl = iev-ibv+1; nxwl = iew-ibw+1; nxpl = iep-ibp+1;
          nyul = jeu-jbu+1; nyvl = jev-jbv+1; nywl = jew-jbw+1; nypl = jep-jbp+1;
          nzul = keu-kbu+1; nzvl = kev-kbv+1; nzwl = kew-kbw+1; nzpl = kep-kbp+1;
          
          % Reconstruct ghost cells
          if x_periodic
            if ibu==1;   ium1=nxu; else; ium1=ibu-1; end
            if ibv==1;   ivm1=nxv; else; ivm1=ibv-1; end
            if ibw==1;   iwm1=nxw; else; iwm1=ibw-1; end
            if ibp==1;   ipm1=nxp; else; ipm1=ibp-1; end
            if ieu==nxu; iup1=1;   else; iup1=ieu+1; end
            if iev==nxv; ivp1=1;   else; ivp1=iev+1; end
            if iew==nxw; iwp1=1;   else; iwp1=iew+1; end
            if iep==nxp; ipp1=1;   else; ipp1=iep+1; end
          else
            if ibu==1;   ium1=1;   else; ium1=ibu-1; end
            if ibv==1;   ivm1=1;   else; ivm1=ibv-1; end
            if ibw==1;   iwm1=1;   else; iwm1=ibw-1; end
            if ibp==1;   ipm1=1;   else; ipm1=ibp-1; end
            if ieu==nxu; iup1=nxu; else; iup1=ieu+1; end
            if iev==nxv; ivp1=nxv; else; ivp1=iev+1; end
            if iew==nxw; iwp1=nxw; else; iwp1=iew+1; end
            if iep==nxp; ipp1=nxp; else; ipp1=iep+1; end
          end
          if y_periodic
            if jbu==1;   jum1=nyu; else; jum1=jbu-1; end
            if jbv==1;   jvm1=nyv; else; jvm1=jbv-1; end
            if jbw==1;   jwm1=nyw; else; jwm1=jbw-1; end
            if jbp==1;   jpm1=nyp; else; jpm1=jbp-1; end
            if jeu==nyu; jup1=1;   else; jup1=jeu+1; end
            if jev==nyv; jvp1=1;   else; jvp1=jev+1; end
            if jew==nyw; jwp1=1;   else; jwp1=jew+1; end
            if jep==nyp; jpp1=1;   else; jpp1=jep+1; end
          else
            if jbu==1;   jum1=1;   else; jum1=jbu-1; end
            if jbv==1;   jvm1=1;   else; jvm1=jbv-1; end
            if jbw==1;   jwm1=1;   else; jwm1=jbw-1; end
            if jbp==1;   jpm1=1;   else; jpm1=jbp-1; end
            if jeu==nyu; jup1=nyu; else; jup1=jeu+1; end
            if jev==nyv; jvp1=nyv; else; jvp1=jev+1; end
            if jew==nyw; jwp1=nyw; else; jwp1=jew+1; end
            if jep==nyp; jpp1=nyp; else; jpp1=jep+1; end
          end
          if z_periodic
            if kbu==1;   kum1=nzu; else; kum1=kbu-1; end
            if kbv==1;   kvm1=nzv; else; kvm1=kbv-1; end
            if kbw==1;   kwm1=nzw; else; kwm1=kbw-1; end
            if kbp==1;   kpm1=nzp; else; kpm1=kbp-1; end
            if keu==nzu; kup1=1;   else; kup1=keu+1; end
            if kev==nzv; kvp1=1;   else; kvp1=kev+1; end
            if kew==nzw; kwp1=1;   else; kwp1=kew+1; end
            if kep==nzp; kpp1=1;   else; kpp1=kep+1; end
          else
            if kbu==1;   kum1=1;   else; kum1=kbu-1; end
            if kbv==1;   kvm1=1;   else; kvm1=kbv-1; end
            if kbw==1;   kwm1=1;   else; kwm1=kbw-1; end
            if kbp==1;   kpm1=1;   else; kpm1=kbp-1; end
            if keu==nzu; kup1=nzu; else; kup1=keu+1; end
            if kev==nzv; kvp1=nzv; else; kvp1=kev+1; end
            if kew==nzw; kwp1=nzw; else; kwp1=kew+1; end
            if kep==nzp; kpp1=nzp; else; kpp1=kep+1; end
          end
         
          % Write u
          %fprintf('%d,%d,%d,%d - %d,%d,%d,%d - %d,%d,%d,%d\n',ium1,ibu,ieu,iup1,jum1,jbu,jeu,jup1,kum1,kbu,keu,kup1);
          %fprintf('%d,%d,%d,%d - %d,%d,%d,%d - %d,%d,%d,%d\n',ivm1,ibv,iev,ivp1,jvm1,jbv,jev,jvp1,kvm1,kbv,kev,kvp1);
          %fprintf('%d,%d,%d,%d - %d,%d,%d,%d - %d,%d,%d,%d\n',iwm1,ibw,iew,iwp1,jwm1,jbw,jew,jwp1,kwm1,kbw,kew,kwp1);
          %fprintf('%d,%d,%d,%d - %d,%d,%d,%d - %d,%d,%d,%d\n',ipm1,ibp,iep,ipp1,jpm1,jbp,jep,jpp1,kpm1,kbp,kep,kpp1);
          tmp = zeros(nxul+2,nyul+2,nzul+2);
          tmp(2:end-1,2:end-1,2:end-1) = u(ibu:ieu,jbu:jeu,kbu:keu);
          tmp(1,:,:)   = u(ium1,[jum1,jbu:jeu,jup1],[kum1,kbu:keu,kup1]);
          tmp(end,:,:) = u(iup1,[jum1,jbu:jeu,jup1],[kum1,kbu:keu,kup1]);
          tmp(:,1,:)   = u([ium1,ibu:ieu,iup1],jum1,[kum1,kbu:keu,kup1]);
          tmp(:,end,:) = u([ium1,ibu:ieu,iup1],jup1,[kum1,kbu:keu,kup1]);
          tmp(:,:,1)   = u([ium1,ibu:ieu,iup1],[jum1,jbu:jeu,jup1],kum1);
          tmp(:,:,end) = u([ium1,ibu:ieu,iup1],[jum1,jbu:jeu,jup1],kup1);
          obj.appendField(tmp,1,ibu,jbu,kbu,nxu,nyu,nzu);
          
          % Write v
          tmp = zeros(nxvl+2,nyvl+2,nzvl+2);
          tmp(2:end-1,2:end-1,2:end-1) = v(ibv:iev,jbv:jev,kbv:kev);
          tmp(1,:,:)   = v(ivm1,[jvm1,jbv:jev,jvp1],[kvm1,kbv:kev,kvp1]);
          tmp(end,:,:) = v(ivp1,[jvm1,jbv:jev,jvp1],[kvm1,kbv:kev,kvp1]);
          tmp(:,1,:)   = v([ivm1,ibv:iev,ivp1],jvm1,[kvm1,kbv:kev,kvp1]);
          tmp(:,end,:) = v([ivm1,ibv:iev,ivp1],jvp1,[kvm1,kbv:kev,kvp1]);
          tmp(:,:,1)   = v([ivm1,ibv:iev,ivp1],[jvm1,jbv:jev,jvp1],kvm1);
          tmp(:,:,end) = v([ivm1,ibv:iev,ivp1],[jvm1,jbv:jev,jvp1],kvp1);
          obj.appendField(tmp,1,ibv,jbv,kbv,nxv,nyv,nzv);
          
          % Write w
          tmp = zeros(nxwl+2,nywl+2,nzwl+2);
          tmp(2:end-1,2:end-1,2:end-1) = w(ibw:iew,jbw:jew,kbw:kew);
          tmp(1,:,:)   = w(iwm1,[jwm1,jbw:jew,jwp1],[kwm1,kbw:kew,kwp1]);
          tmp(end,:,:) = w(iwp1,[jwm1,jbw:jew,jwp1],[kwm1,kbw:kew,kwp1]);
          tmp(:,1,:)   = w([iwm1,ibw:iew,iwp1],jwm1,[kwm1,kbw:kew,kwp1]);
          tmp(:,end,:) = w([iwm1,ibw:iew,iwp1],jwp1,[kwm1,kbw:kew,kwp1]);
          tmp(:,:,1)   = w([iwm1,ibw:iew,iwp1],[jwm1,jbw:jew,jwp1],kwm1);
          tmp(:,:,end) = w([iwm1,ibw:iew,iwp1],[jwm1,jbw:jew,jwp1],kwp1);
          obj.appendField(tmp,1,ibw,jbw,kbw,nxw,nyw,nzw);
          
          % Write p
          tmp = zeros(nxpl+2,nypl+2,nzpl+2);
          tmp(2:end-1,2:end-1,2:end-1) = p(ibp:iep,jbp:jep,kbp:kep);
          tmp(1,:,:)   = p(ipm1,[jpm1,jbp:jep,jpp1],[kpm1,kbp:kep,kpp1]);
          tmp(end,:,:) = p(ipp1,[jpm1,jbp:jep,jpp1],[kpm1,kbp:kep,kpp1]);
          tmp(:,1,:)   = p([ipm1,ibp:iep,ipp1],jpm1,[kpm1,kbp:kep,kpp1]);
          tmp(:,end,:) = p([ipm1,ibp:iep,ipp1],jpp1,[kpm1,kbp:kep,kpp1]);
          tmp(:,:,1)   = p([ipm1,ibp:iep,ipp1],[jpm1,jbp:jep,jpp1],kpm1);
          tmp(:,:,end) = p([ipm1,ibp:iep,ipp1],[jpm1,jbp:jep,jpp1],kpp1);
          obj.appendField(tmp,1,ibp,jbp,kbp,nxp,nyp,nzp);

          obj.close();
          clear obj
        end
      end
    end
end

function [ind] = locfun_proc_id(ii,jj,kk,nx,ny,nz)
  % local version of 'sub2ind_zero_row'
  ind=ii*ny*nz+jj*nz+kk;
end