Adding safety check when accessing list element; fixes #117
Adding safety check when accessing list element; fixes #117

rdebroiz/medInria-public,rdebroiz/medInria-public,aabadie/medInria-public,NicolasSchnitzler/medInria-public,NicolasSchnitzler/medInria-public,NicolasSchnitzler/medInria-public,rdebroiz/medInria-public,aabadie/medInria-public,aabadie/medInria-public