imu initialization question

[lturing]

firstly, thanks for this great work! recently, i read imu initialized codes, i find some questions likes here, take an example

A.block<3, 3>(i * 6, 0) = -0.5 * delta.t * delta.t * matrix<3>::Identity(); i think it should be

A.block<3, 3>(i * 6, 0) += -0.5 * delta.t * delta.t * matrix<3>::Identity(); do i miss some parts?