function [zs, unit]=zscale(header)
%Zscale Return the image Z scale

%
% Copyright (c) 1995 by Claudio Rivetti and Mark Young
% claudio@alice.uoregon.edu,    mark@alice.uoregon.edu
%

zs=getparameter(header, 'Z scale',1);
unit='';
if zs~=inf
  if isstr(zs)
    [scan_num,r]=strtok(zs, ' ');
    zs= str2num(scan_num);
    unit=strtok(r, ' ');
  else
    i=zs(1)+2;
	zs=zs(i);
  end
end

return