@Stefan Schippers , really slow on my system , took ~1hr. Reference value : 9.25600e-10 No. of Data Rows : 59 Total analysis time (seconds) = 15.429 Total elapsed time (seconds) = 3559.600 Total DRAM available = 13064.734 MB. DRAM currently available = 8131.395 MB. Maximum ngspice program size = 1550.543 MB. Current ngspice program size = 1525.125 MB. Shared ngspice pages = 10.285 MB. Text (code) pages = 5.316 MB. Stack = 0 bytes. Library pages = 1523.246 MB. real 59m19.685s user 59m18.425s sys 0m5.822s