function [] = write_uvwp_chunk_ucf(file,...
    u,ibu,jbu,kbu,nxu,nyu,nzu,...
    v,ibv,jbv,kbv,nxv,nyv,nzv,...
    w,ibw,jbw,kbw,nxw,nyw,nzw,...
    p,ibp,jbp,kbp,nxp,nyp,nzp,...
    time,ighost,varargin)
    % [] = write_uvwp_chunk_ucf(file,...
    %  u,ibu,jbu,kbu,nxu,nyu,nzu,,...
    %  v,ibv,jbv,kbv,nxv,nyv,nzv,,...
    %  w,ibw,jbw,kbw,nxw,nyw,nzw,,...
    %  p,ibp,jbp,kbp,nxp,nyp,nzp,,...
    %  time,ighost,varargin)
    % Writes a partial uvwp field to UCF chunk.
    % Input
    %   file                file to be written (the extension will be replaced by the proc rank)
    %   u,v,w,p             partial u,v,w,p fields with dim(nx,ny,nz)
    %   ib,jb,kb            global index of first data point of field w/o ghost cells
    %   nx,ny,nz            global grid size
    %   time                simulation time
    %   ighost              does partial field contain ghost cells?
    % Optional input (key/value pair)
    %   rank                processor rank as array [myid,my_col,my_row,my_pln]
    %   endian              endianess of the file as used by fopen (default: 'n')
    %   verbosity           verbose output? (default: no)
    %   debug               debug output? (default: no)

    % Parse variable input
    par = inputParser;
    addParamValue(par,'rank',[0,0,0,0],@(x)isnumeric(x)&&numel(x)==4);
    addParamValue(par,'endian','n',@ischar);
    addParamValue(par,'verbosity',0,@isnumeric);
    addParamValue(par,'debug',0,@isnumeric);
    parse(par,varargin{:});

    % Create file and write to it
    obj = ucf('verbosity',par.Results.verbosity,'debug',par.Results.debug);
    obj.create(file,'type','field','rank',par.Results.rank,'endian',par.Results.endian);
    obj.appendStep(time);

    % Write u
    nxul = size(u,1)-2*ighost;
    nyul = size(u,2)-2*ighost;
    nzul = size(u,3)-2*ighost;
    params = int64([ighost,ibu,jbu,kbu,nxul,nyul,nzul,nxu,nyu,nzu]);
    obj.appendSet(u,params);

    % Write v
    nxvl = size(v,1)-2*ighost;
    nyvl = size(v,2)-2*ighost;
    nzvl = size(v,3)-2*ighost;
    params = int64([ighost,ibv,jbv,kbv,nxvl,nyvl,nzvl,nxv,nyv,nzv]);
    obj.appendSet(v,params);

    % Write w
    nxwl = size(w,1)-2*ighost;
    nywl = size(w,2)-2*ighost;
    nzwl = size(w,3)-2*ighost;
    params = int64([ighost,ibw,jbw,kbw,nxwl,nywl,nzwl,nxw,nyw,nzw]);
    obj.appendSet(w,params);

    % Write p
    nxpl = size(p,1)-2*ighost;
    nypl = size(p,2)-2*ighost;
    nzpl = size(p,3)-2*ighost;
    params = int64([ighost,ibp,jbp,kbp,nxpl,nypl,nzpl,nxp,nyp,nzp]);
    obj.appendSet(p,params);

    % Close file
    obj.close();
end