function [strain,ts]=load_strain(id,t);

% function [strain,ts]=load_strain(id,t);
%
% load tether strain or submergence from the raw drifter file
%  id: id number from directory file. 
%  t: times

if (length(id)>1) id=id(1); end;

% ityp, file type
%   where 1=raw,2=pos edited, 3=sensor edited, 4-kriged
ityp=1;

[fname,dname,nwd]=dfname(id,ityp);
[nrec,dat]=readfl(1,dname,fname,ityp,min(t),max(t),nwd);
 
if (length(dat))
    
    ts=dat(:,4);
    strain=dat(:,5);
     
    q=find(strain>=999);
    strain(q)=NaN;

else
    ts=NaN; strain=NaN;
end;