function err=errcheck1(n, out, fn, hfile);
%checks error in n
%err=1 if there is error
%err=0 otherwise
%prints message in the file out if there is an error
%out must be opened and closed in the calling program

err=0;
if (length(n) == 0);
  fprintf(out,'error in file %s function %3d.\n', hfile, fn);
  quit;
  err=1;
end;