Ensure user calls addalgo/addwrapper method with output

code/classes/SCDclass_component.m

@@ -18,6 +18,7 @@ classdef SCDclass_component
   methods
    
     function obj = addalgo(obj,algo)
+      assert(nargout==1,'must assign output for addalgo method')
       % add an algorithm object
       assert(isa(algo,'SCDclass_algo'));
       

code/classes/SCDclass_node.m

@@ -41,6 +41,7 @@ classdef SCDclass_node < SCDclass_component
       % varalgo is the variant subsystem number used to select this wrapper
       % isactive (true by default) sets whether the addition of the wrapper
       % also sets the cpu to be active;
+      assert(nargout==1,'must assign output for addwrapper method')
       
       % by default, activate CPU when adding a wrapper
       if nargin==4, isactive=true; end