I have some bulk systems and want to calculate elastic constants. (stress, strain, and stiff matrix along with all the other moduli)

Manual said to deform box in one direction using displace_box and measure the change in the stress tensor.

And also said that examples/elastic directory would contain example input scripts, but there were no elastic directory in example part.

Can any of you give me some hints or input commands that can calculate elastic constants?

Thank you!