samer@4: function a=getparam(s,field,def)
samer@4: % getparam - get value of named field or default if not present
samer@4: %
samer@7: % getparam :: struct Fields, string~'field name', A~'default value' -> A.
samer@4: %
samer@37: % Typical usage is with structures returned by options.
samer@4: 
samer@4: if isfield(s,field), a=s.(field); else a=def; end
samer@4: