Thanks for this answer. Thanks a lot. Could I bother you with one more? Given that I’m going to use the opt.minimize method to minimize a loss function, in tensorflow, one needs to set a var_list argument, which tells the optimizer(SGD etc) which tensors to vary. In that case, i would just add x(and y) to that list, and leave z out, or can i just list z and it can figure out which elements are variables and which are constants ?