When you want a new figure for every one, that pretty-much means splitapply isn't going to be all that handy because you can't define an anonymous function that has more than one line --and you've got to have at least two for the new figure followed by plot. You can write a small inline function and call that, of course, but if doing that, may as well just do it inline -- but you can still use findgroups although as you've discovered, unique works as well or as well could discretize
D=table2array(B);
[g,id]=findgroups(D(:,1));
for i=1:numel(id)
figure
plot(D(D(:,1)==id(i),3),'DisplayName',"Group "+id(i))
end
legend
Virtually the same code you had; splitapply or rowfun for a table just do the lookup indexing for you -- but they're doing the same thing inside, it's just "syntactic sugar" to save you the trouble writing the indexing expression. But, the price for ease is the above -- you can't include more code than one line in an anonymous function so if your needs are more than can be done that way, you have to write another function anyway.
