How to get RMSD from beginning to end after extending simulation

GROMACS version:
GROMACS modification: Yes/No
Here post your question

Dear all,
I performed 150ns simulation and the I extended to another 50 ns (total 200ns). I have faced problems in calculating RMSD from 1ns to 200 ns due to extending the simulation time
My question is,
How can I get RMSD from 1ns to 200 ns?


You can combine the xtc files from the 150 ns and 50 ns simulations using ‘gmx trjcat,’ and then calculate the rmsd for the combined trajectory.