testlist <- list(df = c(-1.66747247732085e-265, 3.1381372091751e-146, 2.51794803343309e+65,  -2.07422478261465e+286, 7.27281562784794e+158, 2.45806146443934e+156,  -2.26463289029504e+51, 2.37920358286569e-87, 2.25271570962966e-291,  1.09819618275991e+130, 6.45595945839617e-99, -6.80240590991958e+120,  5.63101862305434e-258, 3.68411217199538e-128, -2.16833629339867e-81,  -1.68292282855994e+243, -2.84760510974174e-235, -1.11477807749964e-253,  2.18460497179435e+93, -9.28736431958951e-278, -9.08855473933885e-157,  -1.66520904444299e-141, 9.03801679465132e-185, -3.78271411509748e+64,  -3.01205144524744e+64, 1.32140598707239e-137, -1.3292883322375e+39,  NA, 3.27626729416735e-06, 4.88504587369941e+141, 1.5223333738139e-291,  3.62445489617802e-231, 4.28401158909788e+216, -8.64203757841604e-155,  3.78009856442271e-164, -Inf, 2.22324959796964e-23, Inf, 1.25497284988254e+297,  2207837.88386101, 1.35799393219809e-301, -Inf, -1.12338859678405e-129,  -0.0892049943998191, 4.71913272329789e-67, -1.57552403620931e-51,  -8.47145863906654e+163, 0), lmd = c(-4.72722007343954e+56, 6.68538245962256e+231,  3.46037773482931e-81, -4.37897512268896e-62, 1.02570254976333e-201,  -2.11568806253225e+113, -3.53415948859757e-231, NaN, -2.11568806253225e+113,  -2.61195668268438e-299, 4.34152928430398e-107, 9.95563334918271e-177,  3.68943010862686e+170, -1.22279668688982e+194, 0.000427849142573787,  2.83944529088186e-136, -4.93473532743617e-54, -2.11568806253225e+113 ), mu = c(-2.37465471934456e-145, -2.94070504927606e-263, 8.39604175017819e+247,  -1.59665592183567e+207, NA, 657595969804676864, 7.35936658474943e-37,  3.87808032990093e-137, NA, -7.10597869052168e-179, 2.95984900385564e+62,  1.30967595736768e-50, -7.47114250395843e+277, -9.12067793582203e+172,  -1.74718127780681e-15, 2.78768619402098e-216, -3.77047751271239e-217,  -7.72365369275945e-69, 4.81256975152072e-158, 2.06726739377141e+229,  56.9312354878322, 18979690524.8918, 2.25504058620613e+295, 8.94059869730281e-79,  -2.85943504104372e+36, -7.05962784532492e+187, 2.23874215703575e-219,  5.69299511525479e-244, -Inf, -1.69602469429046e-106, -3.07079488470671e+213,  4.5939330040992e-300, 2.72797745065723e+151, 3.789428928249e+242,  -2.35702736056675e+292, 9.52183914834285e+145, 7.40789524773471e+177,  5.04187439736906e-134, 1.22154726749432e+80, 1.01270202365884e+150,  -1.43968571582442e+35, -2.13506931042781e+197, -1.79398971023829e-280,  1.6796230085982e-65, 0), phi = c(2.95463431539047e-46, -7.77337320277531e-225,  5.8189539212319e+295, -1.84249103497878e-100, 6.83525138882369e-108,  1.22494827712845e+252, -3.32925366956403e-85, -2.41870918823378e+232,  -2.58403059157156e+50, -1.77265828733363e-206, 1.59179376251261e-254,  3.35863275127527e-269, -7.30476803374757e-159, -1.3479446984414e-152,  1.4704662097067e+224, 7.09982838791826e+33, -4.49911403994892e+254,  -7.8829187096676e+271, 2.05662786637849e+242, 1.90471103151414e+43,  8.83300914423193e+247, 9.51030849010102e+188, 5.61950904762912e-05,  7.29680314836409e+74, -1.6816220061266e-111, 5.46247087589397e-207,  4.97569444706432e-86, 1.45561033678335e-18, -1.27857031267989e-276,  3.30224849292396e-72, -2.14329202366998e-74, -1.87846499300399e-122,  -1.25066297778969e-31, -2036.52093022688, -5.60640107220591e-88,  9.89207675428853e-206, Inf, 6.1616236149094e-226, 1.09784757765001e-198,  -1.59013313015192e+105, -4.28983702233887e+51, 1.02895941420219e+179,  -3.16965065431155e-19, 5.52709339549281e+47, 2.7098575623785e+141,  -7.56035774406275e-85, -2.68561402540497e-25, -3.79462224360965e-289,  -1.12310802172802e+244, 7.48248499321468e+40, -1.58351983075439e-228,  1.74782124817953e+190, -1.99841175478417e-176, 4.87178089881822e+255,  9.60180108374131e-240, 1.7527539418977e-06, -1.39118068296894e+141,  2.64729370073803e-43, -1.2247063973278e+119, -1.90381386458267e+184,  -4.4678893880166e+95, 9.1527947211778e-290, 9.35061350313042e-187,  -3.00369230551929e-25, -4.27366968500042e-303, 6.53078990979408e-112,  NaN, -403957510359604224, NaN, -2.40380412517095e+73, 1.16206487726149e-91,  -8.22439921141506e+139, 1.47665989610371e-91, 3.97132292281755e+84,  2.64956162975032e+241, -3.29778315694099e-196, 6.52978186620787e+68,  -8.90674981172842e+195, -3.50915500696071e-235, 3.71493451629065e+54,  1.03980570251513e+40, -0.0304746287632138, 1.42656883606422e-42,  4.73039563399502e-36, 2.49654168849689e+243, -2.26276700754823e+68,  3.25474805377448e-21, 7.461217066235e+28, 1.03378341397493e-149,  1.0959650659227e-120, 1.20382482255242e+39, -1.00801398391237e+43,  9.18257091419111e-65, Inf, 2.2614124669118e+195, 2.19640686251724e+217,  0))
result <- do.call(dng:::splitt_mean,testlist)
str(result)