function b = GAisa(G, t)%GAisa(G,t): Return 1 if G is of type t, 0 otherwise%%See also gable.% GABLE, Copyright (c) 1999, University of Amsterdam% Copying, use and development for non-commercial purposes permitted.%          All rights for commercial use reserved; for more information%          contact Leo Dorst (leo@wins.uva.nl).%%          This software is unsupported.m = G.m ~= 0;if sum(abs(m)) == 0  b = 1;elseif strcmp(t,'double')   if sum(m(2:8)) == 0    b = 1;  else    b = 0;  endelseif strcmp(t,'vector')   if sum(m(5:8)) == 0 & G.m(1)==0    b = 1;  else    b = 0;  endelseif strcmp(t,'bivector')   if sum(m(1:4)) == 0 & G.m(8)==0    b = 1;  else    b = 0;  endelseif strcmp(t,'trivector')   if sum(m(1:7)) == 0    b = 1;  else    b = 0;  endelseif strcmp(t,'multivector')  if sum( [sum(m(1)) sum(m(2:4)) sum(m(5:7)) m(8)] ~= 0) > 1    b = 1;   else    b = 0;  endelse  b = 0; % I don't know what they asked for, but it's not usend