%ISSTACKED Test on stacked mapping%%   N = ISSTACKED(W)%   ISSTACKED(W)%% INPUT%   W  Mapping%% OUTPUT%   N  Scalar, 1 if W is a stacked mapping, 0 otherwise%% DESCRIPTION% Returns 1 for stacked mappings. If no output is requested, false outputs% are turned into errors. This may be used for assertion.%% SEE ALSO% ISMAPPING, ISPARALLEL% $Id: isstacked.m,v 1.4 2003/08/18 15:51:54 dick Exp $function n = isstacked(w)	prtrace(mfilename);	if (isa(w,'mapping')) & (strcmp(w.mapping_file,'stacked'))		n = 1;	else		n = 0;	end	% Generate an error if the input is not a stacked mapping and no output 	% is requested (assertion).	if (nargout == 0) & (n == 0)		error([newline '---- Stacked mapping expected -----'])	endreturn