samer@34: function x=dd(x)
samer@34: % dd - convert input sequence or array to sequence
samer@34: %
samer@34: % dd :: [[N,M]] -> seq([[N]]).
samer@34: % dd :: [[N]] -> seq(real).
samer@34: % dd :: seq([[N,M]]) -> seq([[N]]).
samer@34: 
samer@34: if isseq(x)
samer@34: 	if size(x,2)>1, x=concat(map(@slices,x)); end
samer@34: else
samer@34: 	if isscalar(x),     x=repeat(x); 
samer@34: 	else                x=slices(x);
samer@34: 	end
samer@34: end