https://root.cern.ch/doc/master/structROOT_1_1Math_1_1RetrieveMatrix_3_01T_00_01D1_00_01D2_00_01D3_00_01D4_00_01MatRepSym_3_01T_e30ff0328f3a8a31d82ee857be0ae304.html
ROOT: ROOT::Math::RetrieveMatrix T, D1, D2, D3, D4, MatRepSym T, D1 , MatRepStd T, D3, D4 ...
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