Matlab:? Undefined function or method for input arguments of type 'double?

You try to access the variable Z before it was defined. You need to assign a value to Z before accessing its contents.

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.