Why it is input, because this is the existing wave environment, you can say this is the
environmental disturbance that is existing; there this is going to cause a disturbance that
causes my ship to move up and down. So, I have to predict from here to here, given this
find this, this is my objective and that is what is meant by how I find out motion at
irregular waves. So, this is a very interesting part and I will tell you how we go about it.