I am currently implementing a CTM method for iPEPS in ITensor. For this, and similar algorithms, I want to absorb a big bunch of tensors and truncate the result in order to approximate the environment.
For numerical stability, one way to do this is by dividing the updated tensors by its norm or maximal element etc in order to not diverge to infinity or zero. However, for some purpose it might be good to have the tensor not divided by its norm. To stabilize this, I would expect the
scaleTo( ) method to do the job. Playing around with it naively, however,
does only work every now and then. I am not yet sure why that is, but also have not yet got through the whole details behind this method. Moreover, I have the feeling that probably using something like
should work more accurately. Therefore: is there some method that finds the maximal (in absolute value) element within the tensor data?
Best and thanks a lot!