diff --git a/chunkie/+chnk/+helm2d/kern.m b/chunkie/+chnk/+helm2d/kern.m
index 0b535c4..401e0e4 100644
--- a/chunkie/+chnk/+helm2d/kern.m
+++ b/chunkie/+chnk/+helm2d/kern.m
@@ -40,7 +40,7 @@
 %                       [coef(1,1)*D coef(1,2)*S; coef(2,1)*D' coef(2,2)*S']
 %                type == 'c2trans' returns the combined field, and the 
 %                          normal derivative of the combined field
-%                        [coef(1)*D + coef(2)*S; coef(1)*D' + coef(2)*S']
+%                        [coef(1,1)*D + coef(1,2)*S; coef(2,1)*D' + coef(2,2)*S']
 %                type == 'trans_rep' returns the potential corresponding
 %                           to the transmission representation
 %                        [coef(1)*D coef(2)*S]
@@ -250,6 +250,7 @@
 if strcmpi(type,'c2trans') 
   coef = ones(2,1);
   if(nargin == 5); coef = varargin{1}; end
+  if numel(coef) == 2, coef = repmat(coef(:).',2,1); end
   targnorm = targinfo.n(:,:);
   srcnorm = srcinfo.n(:,:);
 
@@ -272,8 +273,8 @@
 
   submat = zeros(2*nt,ns);
 
-  submat(1:2:2*nt,:) = coef(1)*submatd + coef(2)*submats;
-  submat(2:2:2*nt,:) = coef(1)*submatdp + coef(2)*submatsp;
+  submat(1:2:2*nt,:) = coef(1,1)*submatd + coef(1,2)*submats;
+  submat(2:2:2*nt,:) = coef(2,1)*submatdp + coef(2,2)*submatsp;
 
 end
 
diff --git a/chunkie/+chnk/+helm2dquas/green.m b/chunkie/+chnk/+helm2dquas/green.m
index 781b5ff..2aaca02 100644
--- a/chunkie/+chnk/+helm2dquas/green.m
+++ b/chunkie/+chnk/+helm2dquas/green.m
@@ -1,5 +1,5 @@
 function [val,grad,hess] = green(src,targ,zk,kappa,d,sn,l)
-%CHNK.HELM2DQUAS.GREEN evaluate the quasiperiodic helmholtz green's function
+%CHNK.HELM2DQUAS.GREEN evaluate the quasiperiodic Helmholtz Green's function
 % for the given sources and targets
 %
 % Input:
@@ -13,7 +13,6 @@
 [~,nsrc] = size(src);
 [~,ntarg] = size(targ);
 
-
 xs = repmat(src(1,:),ntarg,1);
 ys = repmat(src(2,:),ntarg,1);
 
@@ -40,8 +39,7 @@
 
 npt = size(r,1);
 
-ythresh = d/2;
-% ythresh = d/10;
+ythresh = 2*d/2;
 iclose = abs(ry) < ythresh;
 ifar = ~iclose;
 
@@ -76,23 +74,19 @@
 % beta = sqrt((xi_m.^2-zk^2));
 beta = sqrt(1i*(xi_m-zk)).*sqrt(-1i*(xi_m+zk));
 
-% fhat = exp(-beta.*sqrt(ryfar.^2))./beta.*exp(1i*xi_m.*rxfar)/2;
 fhat = exp(-beta.*sqrt(ryfar.^2) + 1i*xi_m.*rxfar)./(2*beta);
 val(:,ifar,:) = sum(fhat,3)/(d);
 if nargout > 1
 grad(:,ifar,1) = sum(1i*xi_m.*fhat,3)/d;
 grad(:,ifar,2) = sum(-beta.*(sqrt(ryfar.^2)./ryfar).*fhat,3)/d;
-% grad(:,ifar,:) =[gx,gy];
 end
 
 if nargout >2
 hess(:,ifar,1) = sum(-xi_m.^2.*fhat,3)/d;
 hess(:,ifar,2) = sum(-1i*xi_m.*beta.*(sqrt(ryfar.^2)./ryfar).*fhat,3)/d;
 hess(:,ifar,3) = sum((beta.*(sqrt(ryfar.^2)./ryfar)).^2.*fhat,3)/d;
-% hess(:,ifar,:) = [hxx,hxy,hyy];
 end
 
-
 end
 
 alpha = (exp(1i*kappa(:)*d));
@@ -101,7 +95,8 @@
 grad_near = zeros(1,1,2);
 hess_near = zeros(1,1,3);
 if ~isempty(rxclose)
-    for i = -l:l
+    ls = -l:l;
+    for i = ls
         rxi = rxclose - i*d;
         if nargout>2
         [vali,gradi,hessi] = chnk.helm2d.green(zk,[0;0],[rxi.';ryclose.']);
@@ -123,8 +118,7 @@
         val_near = val_near + vali.*alpha.^i;
         end
     end
-    
-    % sn = sn.';
+
     N = size(sn,2)-1;
     ns = (0:N);
     ns_use = (0:N+2);
@@ -149,9 +143,6 @@
     val_far = 0.25*1i*Js(:,:,1).*sn(:,:,1) + 0.5*1i*sum(sn(:,:,2:end).*Js(:,:,2:end-2).*cs(:,:,2:end),3);
     val(:,iclose) = val_near+val_far;
     
-    
-    
-    
     if nargout >1
         DJs = cat(3,-Js(:,:,2),.5*(Js(:,:,1:end-3)-Js(:,:,3:end-1)))*zk;
         ss = (eipn-1./eipn)/2i;
@@ -202,7 +193,5 @@
 if nargout>2
 hess = reshape(quasi_phase.*hess,nkappa*ntarg,nsrc,3);
 end
-% end
-
 end
 
diff --git a/chunkie/+chnk/+helm2dquas/kern.m b/chunkie/+chnk/+helm2dquas/kern.m
index ecb4568..bb5f387 100644
--- a/chunkie/+chnk/+helm2dquas/kern.m
+++ b/chunkie/+chnk/+helm2dquas/kern.m
@@ -46,7 +46,7 @@
 %                       [coef(1,1)*D coef(1,2)*S; coef(2,1)*D' coef(2,2)*S']
 %                type == 'c2trans' returns the combined field, and the 
 %                          normal derivative of the combined field
-%                        [coef(1)*D + coef(2)*S; coef(1)*D' + coef(2)*S']
+%                        [coef(1,1)*D + coef(1,2)*S; coef(2,1)*D' + coef(2,2)*S']
 %                type == 'trans_rep' returns the potential corresponding
 %                           to the transmission representation
 %                        [coef(1)*D coef(2)*S]
@@ -80,6 +80,7 @@
 src = srcinfo.r(:,:);
 targ = targinfo.r(:,:);
 
+
 kappa = quas_param.kappa;
 d = quas_param.d;
 l = quas_param.l;
@@ -111,13 +112,6 @@
   submat = (grad(:,:,1).*nx + grad(:,:,2).*ny);
 end
 
-% x derivative of single layer
-if strcmpi(type,'sx')
-  [~,grad] = chnk.helm2dquas.green(src,targ,zk,kappa,d,sn,l);
-
-  submat = (grad(:,:,1));
-end
-
 % single later
 if strcmpi(type,'s')
   submat = chnk.helm2dquas.green(src,targ,zk,kappa,d,sn,l);
@@ -145,21 +139,21 @@
 % gradient of single layer
 if strcmpi(type,'sgrad')
     [~,grad] = chnk.helm2dquas.green(src,targ,zk,kappa,d,sn,l);
-    submat = reshape(permute(grad,[3,1,2]),[],ns);
+    submat = reshape(permute(grad,[1,3,2]),[],ns);
 end
 
 % gradient of double layer
 if strcmpi(type,'dgrad')
     [~,~,hess] = chnk.helm2dquas.green(src,targ,zk,kappa,d,sn,l);
     submat = -(hess(:,:,1:2).*reshape(srcinfo.n(1,:),1,[],1)+hess(:,:,2:3).*reshape(srcinfo.n(2,:),1,[],1));
-    submat = reshape(permute(submat,[3,1,2]),[],ns);
+    submat = reshape(permute(submat,[1,3,2]),[],ns);
 end
 
 % Combined field 
 if strcmpi(type,'c')
   srcnorm = srcinfo.n(:,:);
   coef = ones(2,1);
-  if(nargin == 6); coef = varargin{1}; end
+  if(nargin >= 6); coef = varargin{1}; end
   [submats,grad] = chnk.helm2dquas.green(src,targ,zk,kappa,d,sn,l);
   nx = repmat(srcnorm(1,:),nkappa*nt,1);
   ny = repmat(srcnorm(2,:),nkappa*nt,1);
@@ -170,7 +164,7 @@
 % normal derivative of combined field
 if strcmpi(type,'cprime')
   coef = ones(2,1);
-  if(nargin == 6); coef = varargin{1}; end
+  if(nargin >= 6); coef = varargin{1}; end
   targnorm = targinfo.n(:,:);
   srcnorm = srcinfo.n(:,:);
 
@@ -196,8 +190,9 @@
 
 % Dirichlet and neumann data corresponding to combined field
 if strcmpi(type,'c2trans') 
-  coef = ones(2,1);
-  if(nargin == 6); coef = varargin{1}; end
+  coef = ones(1,2);
+  if(nargin >= 6); coef = varargin{1}; end
+  if numel(coef) == 2, coef = repmat(coef(:).',2,1); end
   targnorm = targinfo.n(:,:);
   srcnorm = srcinfo.n(:,:);
 
@@ -220,23 +215,26 @@
   % D
   submatd = -(grad(:,:,1).*nxsrc + grad(:,:,2).*nysrc);
 
-  submat = zeros(nkappa*2*nt,ns);
-
-  submat(1:2:end,:) = coef(1)*submatd + coef(2)*reshape(submats,[],ns);
-  submat(2:2:end,:) = coef(1)*submatdp + coef(2)*submatsp;
+  % submat = zeros(nkappa*2*nt,ns);
+  % submat(1:2:end,:) = coef(1)*submatd + coef(2)*reshape(submats,[],ns);
+  % submat(2:2:end,:) = coef(1)*submatdp + coef(2)*submatsp;
 
+  submat = zeros(nkappa,2,nt,ns);
+  submat(:,1,:,:) = reshape(coef(1,1)*submatd + coef(1,2)*reshape(submats,[],ns),nkappa,1,nt,[]);
+  submat(:,2,:,:) = reshape(coef(2,1)*submatdp + coef(2,2)*submatsp,nkappa,1,nt,[]);
+  submat = reshape(submat, [],ns);
 end
 
 % gradient of combined field
 if strcmpi(type,'cgrad')
     coef = ones(2,1);
-    if(nargin == 6); coef = varargin{1}; end
+    if(nargin >= 6); coef = varargin{1}; end
     [~,grad,hess] = chnk.helm2dquas.green(src,targ,zk,kappa,d,sn,l);
 
-    submats = reshape(permute(grad,[3,1,2]),[],ns);
+    submats = reshape(permute(grad,[1,3,2]),[],ns);
 
     submatd = -(hess(:,:,1:2).*srcinfo.n(1,:)+hess(:,:,2:3).*srcinfo.n(2,:));
-    submatd = reshape(permute(submatd,[3,1,2]),[],ns);
+    submatd = reshape(permute(submatd,[1,3,2]),[],ns);
     
     submat = coef(1)*submatd + coef(2)*submats;
 end
@@ -269,26 +267,27 @@
   % D
   submatd  = -(grad(:,:,1).*nxsrc + grad(:,:,2).*nysrc);
   
-  submat = zeros(nkappa*2*nt,2*ns);
-  submat(1:2:end,1:2:2*ns) = submatd*cc(1,1);
-  submat(1:2:end,2:2:2*ns) = submats*cc(1,2);
-  submat(2:2:end,1:2:2*ns) = submatdp*cc(2,1);
-  submat(2:2:end,2:2:2*ns) = submatsp*cc(2,2);
+  submat = zeros(nkappa,2,nt,2*ns);
+  submat(:,1,:,1:2:2*ns) = reshape(submatd,nkappa,1,nt,[])*cc(1,1);
+  submat(:,1,:,2:2:2*ns) = reshape(submats,nkappa,1,nt,[])*cc(1,2);
+  submat(:,2,:,1:2:2*ns) = reshape(submatdp,nkappa,1,nt,[])*cc(2,1);
+  submat(:,2,:,2:2:2*ns) = reshape(submatsp,nkappa,1,nt,[])*cc(2,2);
+  submat = reshape(submat, [],2*ns);
 end
 % Dirichlet data/potential correpsonding to transmission rep
 if strcmpi(type,'trans_rep') 
 
   coef = ones(2,1);
-  if(nargin == 6); coef = varargin{1}; end;
+  if(nargin >= 6); coef = varargin{1}; end;
   srcnorm = srcinfo.n(:,:);
   [submats,grad,hess] = chnk.helm2dquas.green(src,targ,zk,kappa,d,sn,l);
 
   submats = reshape(submats,[],ns);
-  nx = repmat(srcnorm(1,:),nt,1);
-  ny = repmat(srcnorm(2,:),nt,1);
-  submatd = -(grad(:,:,1).*nx + grad(:,:,2).*ny);
+  nxsrc = repmat(srcnorm(1,:),nkappa*nt,1);
+  nysrc = repmat(srcnorm(2,:),nkappa*nt,1);
+  submatd = -(grad(:,:,1).*nxsrc + grad(:,:,2).*nysrc);
 
-  submat = zeros(nkappa*nt,2*ns);
+  submat = zeros(nkappa*nt,2*ns,'like',1i);
   submat(1:1:end,1:2:2*ns) = coef(1)*submatd;
   submat(1:1:end,2:2:2*ns) = coef(2)*submats;
 end
@@ -296,7 +295,7 @@
 % Neumann data corresponding to transmission rep
 if strcmpi(type,'trans_rep_prime')
   coef = ones(2,1);
-  if(nargin == 6); coef = varargin{1}; end;
+  if(nargin >= 6); coef = varargin{1}; end;
   targnorm = targinfo.n(:,:);
   srcnorm = srcinfo.n(:,:);
   
@@ -305,10 +304,12 @@
   % Get gradient and hessian info
   [submats,grad,hess] = chnk.helm2dquas.green(src,targ,zk,kappa,d,sn,l);
 
-  nxsrc = repmat(srcnorm(1,:),nt,1);
-  nysrc = repmat(srcnorm(2,:),nt,1);
-  nxtarg = repmat((targnorm(1,:)).',1,ns);
-  nytarg = repmat((targnorm(2,:)).',1,ns);
+  nxsrc = repmat(srcnorm(1,:),nkappa*nt,1);
+  nysrc = repmat(srcnorm(2,:),nkappa*nt,1);
+  nxtarg = repmat(reshape(targnorm(1,:),1,nt,1),nkappa,1,ns);
+  nxtarg = reshape(nxtarg,[],ns);
+  nytarg = repmat(reshape(targnorm(2,:),1,nt,1),nkappa,1,ns);
+  nytarg = reshape(nytarg,[],ns);
 
   % D'
   submatdp = -(hess(:,:,1).*nxsrc.*nxtarg ...
@@ -324,7 +325,7 @@
 % Gradient correpsonding to transmission rep
 if strcmpi(type,'trans_rep_grad')
   coef = ones(2,1);
-  if(nargin == 6); coef = varargin{1}; end;
+  if(nargin >= 6); coef = varargin{1}; end;
   
   srcnorm = srcinfo.n(:,:);
   
@@ -332,18 +333,19 @@
   % S
   [submats,grad,hess] = chnk.helm2dquas.green(src,targ,zk,kappa,d,sn,l);
 
-  nxsrc = repmat(srcnorm(1,:),nt,1);
-  nysrc = repmat(srcnorm(2,:),nt,1);
+  nxsrc = repmat(srcnorm(1,:),nkappa*nt,1);
+  nysrc = repmat(srcnorm(2,:),nkappa*nt,1);
   % D
   submatd  = -(grad(:,:,1).*nxsrc + grad(:,:,2).*nysrc);
 
-  submat = zeros(nkappa*2*nt,2*ns);
+  submat = zeros(nkappa,2*nt,2*ns);
   
-  submat(1:2:end,1:2:2*ns) = -coef(1)*(hess(:,:,1).*nxsrc + hess(:,:,2).*nysrc);
-  submat(1:2:end,2:2:2*ns) = coef(2)*grad(:,:,1);
+  submat(:,1,1:2:2*ns) = -coef(1)*(hess(:,:,1).*nxsrc + hess(:,:,2).*nysrc);
+  submat(:,1,2:2:2*ns) = coef(2)*grad(:,:,1);
     
-  submat(2:2:end,1:2:2*ns) = -coef(1)*(hess(:,:,2).*nxsrc + hess(:,:,3).*nysrc);
-  submat(2:2:end,2:2:2*ns) = coef(2)*grad(:,:,2);
+  submat(:,2,1:2:2*ns) = -coef(1)*(hess(:,:,2).*nxsrc + hess(:,:,3).*nysrc);
+  submat(:,2,2:2:2*ns) = coef(2)*grad(:,:,2);
+  submat = reshape(submat,nkappa*2*nt,2*ns);
 end
 
 
diff --git a/chunkie/@chunker/chunker.m b/chunkie/@chunker/chunker.m
index 3e3aa6c..0a644cb 100644
--- a/chunkie/@chunker/chunker.m
+++ b/chunkie/@chunker/chunker.m
@@ -56,6 +56,7 @@
 %   quiver(obj,varargin) - quiver plot of the chnkr points and normals
 %   scatter(obj,varargin) - scatter plot of the chnkr nodes
 %   tau = taus(obj) - unit tangents to curve
+%   cgrph = tochunkgraph(obj) - convert to chunkgraph
 %   obj = refine(obj,varargin) - refine the curve
 %   a = area(obj) - for a closed curve, area inside 
 %   s = arclength(obj) - get values of arclength along curve
@@ -363,6 +364,7 @@
         quiver(obj,varargin)
         scatter(obj,varargin)
         tau = taus(obj)
+        cgrph = tochunkgraph(obj)
         obj = refine(obj,varargin)
         a = area(obj)
         s = arclength(obj)
@@ -377,7 +379,6 @@
         obj = mtimes(A,obj)
         obj = rotate(obj,theta,r0,r1)
         obj = reflect(obj,theta,r0,r1)
-        du = arclengthder(obj,u)
     end
     methods(Static)
         obj = chunkerfunc(fcurve,varargin)
diff --git a/chunkie/@chunker/tochunkgraph.m b/chunkie/@chunker/tochunkgraph.m
new file mode 100644
index 0000000..ea49e94
--- /dev/null
+++ b/chunkie/@chunker/tochunkgraph.m
@@ -0,0 +1,50 @@
+function cgrph = tochunkgraph(chnkr)
+% TOCHUNKGRAPH converts a chunker into a chunkgraph with one edge per
+% connected component
+
+chnkr = sort(chnkr);
+[~,~,info] = sortinfo(chnkr);
+
+ncomp = info.ncomp;
+nchs = info.nchs;
+
+istart = 1;
+nverts = 0;
+verts = [];
+edge2verts = [];
+cparams = cell(1,ncomp);
+fchnks = cell(1,ncomp);
+
+for i = 1:ncomp
+    nch = nchs(i);
+    vs = chunkends(chnkr,[istart,istart+nch-1]);
+    
+    ifclosed = info.ifclosed(i);
+    if ifclosed
+        vs = vs(:,1);
+        verts = [verts, vs];
+        edge2verts = [edge2verts, [nverts+1;nverts+1]];
+        nverts = nverts + 1;
+    else
+        vs = vs(:, [1,4]);
+        verts = [verts, vs];
+        edge2verts = [edge2verts, [nverts+1;nverts+2]];
+        nverts = nverts + 2;
+    end
+
+    rchnkr = []; 
+    rchnkr.r  = chnkr.r(:,:,istart:(istart+nch-1));
+    rchnkr.d  = chnkr.d(:,:,istart:(istart+nch-1));
+    rchnkr.d2 = chnkr.d2(:,:,istart:(istart+nch-1));
+    fchnks{i} = chunkerpoints(rchnkr,struct('ifclosed',ifclosed));
+    cparams{i}.ifclosed = ifclosed;
+    istart = istart + nch;
+end
+
+pref = [];
+
+pref.dim = chnkr.dim;
+pref.k   = chnkr.k;
+cgrph = chunkgraph(verts,edge2verts,fchnks,cparams,pref);
+
+end
\ No newline at end of file
diff --git a/chunkie/@chunkgraph/chunkgraph.m b/chunkie/@chunkgraph/chunkgraph.m
index fe5809b..d719bd1 100644
--- a/chunkie/@chunkgraph/chunkgraph.m
+++ b/chunkie/@chunkgraph/chunkgraph.m
@@ -67,7 +67,6 @@
 %           using bounding rectangles
 %   flag = flagnear_rectangle_grid(obj,x,y) - find points defined via 
 %      a meshgrid of points that are close to the chunkgraph
-%   obj = obj.move(r0,r1,trotat,scale) - translate, rotate, etc
 %   rmin = min(obj) - minimum of coordinate values
 %   rmax = max(obj) - maximum of coordinate values
 %   onesmat = onesmat(obj) - matrix that corresponds to integration of a
@@ -94,14 +93,14 @@
 %   edgesendverts - (2 x nedges) array specifying starting and ending
 %     vertices of an edge. 
 % Optional input:
-%   fchnks - (nedges x 1) cell array of function handles, specifying a
-%     smooth curve to connect the given vertices. fchnk{j} should be a
-%     function in the format expected by CHUNKERFUNC but with the default
-%     that fchnk{j} is a function from [0,1] to the curve. If the specified
-%     curve does not actually connect the given vertices, the curve will be
-%     translated, rotated, and scaled to connect them. If the specified
-%     curve should be a loop, it is only translated to start at the correct
-%     vertex. 
+%   fchnks - (1 x nedges) cell array of function handles or chunkers,
+%     specifying a smooth curve to connect the given vertices. If fchnk{j}
+%     is a function handle, it should be a function in the format expected
+%     by CHUNKERFUNC but with the default that fchnk{j} is a function from
+%     [0,1] to the curve. If the specified curve does not actually connect
+%     the given vertices, the curve will be translated, rotated, and scaled
+%     to connect them. If the specified curve should be a loop, it is only
+%     translated to start at the correct vertex.
 %   cparams - struct or (nedges x 1) cell array of structs specifying curve
 %     parameters in the format expected by CHUNKERFUNC. 
 %   pref - struct specifying CHUNKER preferences. 
@@ -179,7 +178,7 @@
                 fchnks = [];
             end
             
-            if isa(fchnks,"function_handle")
+            if isa(fchnks,"function_handle") || isa(fchnks,"chunker")
                 fchnks0 = fchnks;
                 fchnks = cell(nedge,1);
                 for j = 1:nedge
@@ -242,7 +241,7 @@
                     chnkr = sort(chnkr);
                     %chnkr.vert = [v1,v2];
                     echnks(i) = chnkr;
-                elseif (~isempty(fchnks{i}) && isa(fchnks{i},'function_handle'))
+                else
                     if iscell(cparams)
                         cploc = cparams{i};
                     else
@@ -250,46 +249,71 @@
                     end
                     % set cploc.ifclosed in a way that makes sense
                     cploc.ifclosed = false;
+
                     i1 = edgesendverts(1,i);
                     i2 = edgesendverts(2,i);
-
                     if isnan(i1) || isnan(i2)
                         cploc.ifclosed = true;
                     end
 
-                    % chunkgraph edges need at least 4 chunks
-                    if isfield(cploc,'nchmin')
-                        cploc.nchmin = max(4,cploc.nchmin);
-                    else
-                        cploc.nchmin = 4;
-                    end
-                    
-                    ta = 0; tb = 1;
-                    if isfield(cploc,'ta')
-                        ta = cploc.ta; 
-                    else
-                        cploc.ta = ta;
-                    end
-                    if isfield(cploc,'tb')
-                        tb = cploc.tb; 
-                    else
-                        cploc.tb = tb;
-                    end
 
-                    vs =fchnks{i}([ta,tb]);
-                    if isfield(cploc,'maxchunklen')
-                        if ~isnan(i1) && ~isnan(i2)
-                            if i1 ~= i2 
-                                vfin0 = verts(:,i1);
-                                vfin1 = verts(:,i2);
-                                scale = norm(vfin1-vfin0,'fro')/norm(vs(:,2)-vs(:,1),'fro');
-                                cploc.maxchunklen = cploc.maxchunklen/scale;
+                    if isa(fchnks{i},'function_handle')
+
+    
+                        % chunkgraph edges need at least 4 chunks
+                        if isfield(cploc,'nchmin')
+                            cploc.nchmin = max(4,cploc.nchmin);
+                        else
+                            cploc.nchmin = 4;
+                        end
+                        
+                        ta = 0; tb = 1;
+                        if isfield(cploc,'ta')
+                            ta = cploc.ta; 
+                        else
+                            cploc.ta = ta;
+                        end
+                        if isfield(cploc,'tb')
+                            tb = cploc.tb; 
+                        else
+                            cploc.tb = tb;
+                        end
+    
+                        vs =fchnks{i}([ta,tb]);
+                        if isfield(cploc,'maxchunklen')
+                            if ~isnan(i1) && ~isnan(i2)
+                                if i1 ~= i2 
+                                    vfin0 = verts(:,i1);
+                                    vfin1 = verts(:,i2);
+                                    scale = norm(vfin1-vfin0,'fro')/norm(vs(:,2)-vs(:,1),'fro');
+                                    cploc.maxchunklen = cploc.maxchunklen/scale;
+                                end
                             end
                         end
+                        
+                        chnkr = chunkerfunc(fchnks{i}, cploc, pref);
+
+                    elseif isa(fchnks{i},'chunker')
+                        chnkr = fchnks{i};
+                        [~,~,info] = sortinfo(chnkr);
+                        if info.ncomp > 1
+                            msg = "CHUNKGRAPH:CONSTRUCTOR: invalid edge descriptor." + ...
+                                  " fchnks{" + num2str(i) + "} must be a " + ...
+                                  "single connected component.";
+                            warning(msg);
+                        end
+
+                        vs = chunkends(chnkr,[1,chnkr.nch]);
+                        vs = vs(:, [1,4]);
+
+                    else
+                        msg = "CHUNKGRAPH:CONSTRUCTOR: invalid edge descriptor." + ...
+                              " fchnks{" + num2str(i) + "} must be empty, a" + ...
+                              " function handle, or a chunker.";
+                        warning(msg);
                     end
-                    
-                    chnkr = chunkerfunc(fchnks{i}, cploc, pref);
                     chnkr = sort(chnkr);
+
                     if ~isnan(i1) && ~isnan(i2)
                         if i1 ~= i2 
                             vfin0 = verts(:,i1);
@@ -317,7 +341,6 @@
                             chnkr = move(chnkr,zeros(size(vs(:,1))),vfin-vs(:,1),0,1);
                         end
                     end
-
                     echnks(i) = chnkr;
                 end
             end
diff --git a/chunkie/@kernel/helm2dquas.m b/chunkie/@kernel/helm2dquas.m
index d71db42..a469177 100644
--- a/chunkie/@kernel/helm2dquas.m
+++ b/chunkie/@kernel/helm2dquas.m
@@ -60,7 +60,7 @@
 l=2; N = 40; a = 15; M = 1e4;
 
 if nargin == 6
-    if isefield(quad_opts,'l')
+    if isfield(quad_opts,'l')
         l = quad_opts.l;
     end
     if isfield(quad_opts,'N')
@@ -83,11 +83,6 @@
 quas_param.l = l;
 quas_param.sn = sn;
 
-% obj.params.kappa = kappa;
-% obj.params.d = d;
-% obj.params.l = l;
-% obj.params.Sn = Sn;
-
 obj.params.quas_param = quas_param;
 
 switch lower(type)
@@ -160,7 +155,6 @@
         error('Unknown Helmholtz kernel type ''%s''.', type);
 
 end
-
 end
 
 function f = helm2dquas_s_split(zk,s,t,quas_param)
diff --git a/devtools/test/quasiperiodicTest.m b/devtools/test/quasiperiodicTest.m
index e30fedd..30302aa 100644
--- a/devtools/test/quasiperiodicTest.m
+++ b/devtools/test/quasiperiodicTest.m
@@ -68,10 +68,10 @@ function quasiperiodicTest0()
 
 % test all
 all_assemb = zeros(size(allval));
-all_assemb(1:2:end, 1:2:end) = coefa(1,1)*dval;
-all_assemb(1:2:end, 2:2:end) = coefa(1,2)*sval;
-all_assemb(2:2:end, 1:2:end) = coefa(2,1)*dpval;
-all_assemb(2:2:end, 2:2:end) = coefa(2,2)*spval;
+all_assemb(1:2, 1:2:end) = coefa(1,1)*dval;
+all_assemb(1:2, 2:2:end) = coefa(1,2)*sval;
+all_assemb(3:end, 1:2:end) = coefa(2,1)*dpval;
+all_assemb(3:end, 2:2:end) = coefa(2,2)*spval;
 assert(norm(all_assemb - allval) <  1e-12)
 
 % test transmission representiatoon
@@ -84,8 +84,8 @@ function quasiperiodicTest0()
 
 % test c2trans
 c2trval_assemb = zeros(size(c2trval));
-c2trval_assemb(1:2:end, :) = coefs(1)*dval + coefs(2)*sval;
-c2trval_assemb(2:2:end, :) = coefs(1)*dpval + coefs(2)*spval;
+c2trval_assemb(1:2, :) = coefs(1)*dval + coefs(2)*sval;
+c2trval_assemb(3:end, :) = coefs(1)*dpval + coefs(2)*spval;
 assert(norm(c2trval_assemb-c2trval) <  1e-12)
 end
 
@@ -97,7 +97,7 @@ function quasiperiodicTest1()
 % problem parameters
 d= 8;
 zk = 1;
-kappa = .05+0.1i;
+kappa = .05+.1i;
 
 % setup geometry
 nch = 2^3;
diff --git a/devtools/test/tochunkgraphTest.m b/devtools/test/tochunkgraphTest.m
new file mode 100644
index 0000000..5cb31b7
--- /dev/null
+++ b/devtools/test/tochunkgraphTest.m
@@ -0,0 +1,62 @@
+tochunkgraphTest0();
+
+function tochunkgraphTest0()
+%TOCHUNKGRAPHTEST tests the routine for converting chunkers to chunkgraphs
+
+seed = 8675309;
+rng(seed);
+
+% geometry parameters and construction
+
+
+cparams = [];
+cparams.eps = 1.0e-9;
+pref = []; 
+pref.k = 16;
+narms = 0;
+amp = 0.0;
+% make a circle
+chnkr = chunkerfunc(@(t) starfish(t,narms,amp),cparams,pref);
+
+% make an open arc
+cparams.ifclosed = 0;
+chnkr2 = chunkerfunc(@(t) cos_func(t,pi,1),cparams,pref);
+chnkr2 = move(chnkr2,[0;3]);
+
+% merge arcs
+chnkrs(3) = chunker();
+chnkrs(1) = chnkr;
+rfac = 1.1;
+chnkrs(2) = move(chnkr, [0;0], [3;0], 0, rfac);
+chnkrs(3) = chnkr2;
+chnkrtotal = merge(chnkrs);
+
+% form chunkgraph
+cgrph = tochunkgraph(chnkrtotal);
+
+assert(size(cgrph.verts,2) == 4)
+assert(length(cgrph.echnks) == 3)
+assert(cgrph.npt == chnkrtotal.npt)
+assert(norm(cgrph.echnks(1).r(:) - chnkr2.r(:))<1e-14)
+
+verts = [[0;0],[1;1],[3;0]]; edge2verts = [[1;2],[3;3]];
+cgrph = chunkgraph(verts,edge2verts,{chnkr2,chnkr});
+assert(isequal(cgrph.verts,verts))
+assert(isequal(cgrph.edgesendverts,edge2verts))
+
+% verify chunker shifted and scaled correctly 
+vend = cgrph.echnks(1).r(:,1);
+assert(norm(vend-verts(:,1)) < 1e-2);
+
+vend = cgrph.echnks(1).r(:,end);
+assert(norm(vend-verts(:,2)) < 1e-2);
+
+end
+
+function [r,d,d2] = cos_func(t,d,A)
+% parameterization of sinusoidal boundary with period d and amplitude A
+omega = 2*pi/d;
+r = [t(:), A*cos(omega*t(:))].';
+d = [ones(length(t),1), -omega*A*sin(omega*t(:))].';
+d2 = [zeros(length(t),1), -omega^2*A*cos(omega*t(:))].';
+end
\ No newline at end of file