diff --git a/crpptbx/TCV/gdat_tcv.m b/crpptbx/TCV/gdat_tcv.m
index 892b34798f41e9892d58c59b9a409b867ccaedda..c4e39ca04ea6257a63e3e31af7062098294c5a6b 100644
--- a/crpptbx/TCV/gdat_tcv.m
+++ b/crpptbx/TCV/gdat_tcv.m
@@ -1108,7 +1108,7 @@ elseif strcmp(mapping_for_tcv.method,'switchcase')
     % psiscatvol obtained from linear interpolation in fact so not quite ok near axis where psi is quadratic
     recompute_psiscatvol_always = 1;
     if liuqe_version==-1; recompute_psiscatvol_always = 1; end
-    if abs(zshift)<1e-5 && liuqe_matlab==0 && recompute_psiscatvol_always==0
+    if all(abs(zshift)<1e-5) && liuqe_matlab==0 && recompute_psiscatvol_always==0
       psi_max=gdat_tcv([],['\results::thomson' edge_str_dot ':psi_max' substr_liuqe],'nverbose',gdat_params.nverbose);
       psiscatvol=gdat_tcv([],['\results::thomson' edge_str_dot ':psiscatvol' substr_liuqe],'nverbose',gdat_params.nverbose);
     else
@@ -1137,19 +1137,19 @@ elseif strcmp(mapping_for_tcv.method,'switchcase')
        case length(psitdi.dim{3})
         % ok
        case length(gdat_data.t)
-        zeffshift=interp1(psiscatvol.dim{1},zeffshift,psitdi.dim{3});
+        zeffshift=interp1(gdat_data.t,zeffshift,psitdi.dim{3});
        otherwise
         if (gdat_params.nverbose>=1);
           disp(' bad time dimension for zshift')
-          disp(['it should be 1 or ' num2str(length(psiscatvol.dim{1})) ' or ' num2str(length(psitdi.dim{3}))])
+          disp(['it should be 1 or ' num2str(length(gdat_data.t)) ' or ' num2str(length(psitdi.dim{3}))])
         end
       end
       for it=1:length(gdat_data.t)
         itpsitdi=iround_os(psitdi.dim{3},gdat_data.t(it));
         psirz=psitdi.data(:,:,itpsitdi);
-        %psiscatvol0=griddata(rmesh,zmesh,psirz',0.9*ones(size(zthom)),zthom-zeffshift(itpsitdi),'cubic'); % faster with interpos
+        %psiscatvol0=interp2(rmesh,zmesh,psirz',0.9*ones(size(zthom)),zthom-zeffshift(itpsitdi),'spline'); % faster with interpos
         psiscatvol0=interpos2Dcartesian(rmesh,zmesh,psirz,0.9*ones(size(zthom)),zthom-zeffshift(itpsitdi),-0.1,-0.1);
-        psiscatvol0=griddata(rmesh,zmesh,psirz',0.9*ones(size(zthom)),zthom-zeffshift(itpsitdi),'linear');
+        psiscatvol0=interp2(rmesh,zmesh,psirz',0.9*ones(size(zthom)),zthom-zeffshift(itpsitdi),'linear');
         psiscatvol.data(it,:)=psiscatvol0;
         % since take closest psi(R,Z) from psitdi, should also take closest for psi_max and not interpolating
         itpsiaxis = iround_os(psiaxis.dim{1},gdat_data.t(it));