function [MITprofSub]=MITprof_subset(MITprof,varargin);
%   [MITprofSub]=MITprof_subset(MITprof,'depth',[50 150]);
%       returns the subset of MITprof that has prof_depth>=50 and <150
%   [MITprofSub]=MITprof_subset(MITprof,'depth',[50 150],'descr',platformName);
%       ... and prof_descr=platformName;

MITprofSub=MITprof;
fldNames=fieldnames(MITprof);

nSub=(nargin-1)/2;
for iSub=1:nSub;
    eval(['prof_sub=MITprof.prof_' varargin{(iSub-1)*2+1} ';']);
    range_sub=varargin{(iSub-1)*2+2};
    if strcmp('descr',varargin{(iSub-1)*2+1});
        KK=find(strcmp(prof_sub,range_sub));
    elseif strcmp('depth',varargin{(iSub-1)*2+1});
        KK=find(prof_sub>=range_sub(1)&prof_sub<range_sub(2));
    else;
        KK=find(prof_sub>=range_sub(1)&prof_sub<range_sub(2));
    end;
    %  [varargin{(iSub-1)*2+1} ' -- ' num2str(length(KK))]
    for iFld=1:length(fldNames);
        eval(['tmp1=MITprofSub.' fldNames{iFld} ';']);
        if strcmp('depth',varargin{(iSub-1)*2+1}) & strcmp(fldNames{iFld},'prof_depth');
            tmp1=tmp1(KK);
        elseif strcmp('depth',varargin{(iSub-1)*2+1});
            if size(tmp1,2)==length(MITprof.prof_depth); tmp1=tmp1(:,KK); end;
        else;
            if size(tmp1,1)==size(prof_sub,1); tmp1=tmp1(KK,:); end;
        end;
        eval(['MITprofSub.' fldNames{iFld} '=tmp1;']);
    end;
    
end;

%add a couple things:
%--------------------
MITprofSub.np=length(MITprofSub.prof_lon);
MITprofSub.nr=length(MITprofSub.prof_depth);