tryin analyze a 3d truss

im trying to create a matrix for this 3d truss

here is what i have so far

i keep getting this error message what am i doing wrong. what do i still need to do

Answer 1

[Alan Stevens]

Your matrix "connectivity" has 12 rows, but only 2 columns, yet you are trying to access the third (4'th, 5'th ...12'th) column.