diff --git a/matlab/TCV/gdat_tcv.m b/matlab/TCV/gdat_tcv.m
index 11023819e8e91a2c040cf5ba609dc47a6a48855f..b4e524f427ecf5ff4a435439a6a1a24af9f9d9a5 100644
--- a/matlab/TCV/gdat_tcv.m
+++ b/matlab/TCV/gdat_tcv.m
@@ -829,6 +829,7 @@ elseif strcmp(mapping_for_tcv.method,'switchcase')
    case {'b0'}
     % B0 at R0=0.88
     r0exp=0.88;
+    added_correction_str='';
     if isfield(gdat_data.gdat_params,'source') && ~isempty(gdat_data.gdat_params.source) ...
           && length(gdat_data.gdat_params.source)>=5 && strcmp(lower(gdat_data.gdat_params.source(1:5)),'liuqe')
       % expect liuqe or liuqe.m to have liuqe time-base, otherwise give full time base