QuantumATK Forum

QuantumATK => General Questions and Answers => Topic started by: Roc on January 5, 2009, 12:47

Title: some question about the out document
Post by: Roc on January 5, 2009, 12:47

Dear everyone,

In the out document as follows,

# -----------------------------------------------------------------------------
# Energy Spectrum
# -----------------------------------------------------------------------------
# Energy (eV)
       -21.89
       -19.75
       .........
        83.74
        84.39
        84.39
[array([  1.96681012e-01,   5.99825296e-24,  -2.78097762e-24]), array([  1.96681012e-01,   1.58750525e-24,  -7.23663503e-24])]

What does "[array([  1.96681012e-01,   5.99825296e-24,  -2.78097762e-24]), array([  1.96681012e-01,   1.58750525e-24,  -7.23663503e-24])][/b]" mean?

Thanks!

Title: Re: some question about the out document
Post by: Nordland on January 5, 2009, 13:53

I think you have placed a print in your script/program.
An array is numpy storage object used by ATK/NL. It is simply the raw numbers you printed. So I think you have added something like print .... to your script on one of the objects.

But not worries, it does not harm your calculations, only mesh up your output :)

Title: Re: some question about the out document
Post by: Roc on January 6, 2009, 01:15

Thanks, Nordland. You are  very kind! ;) :)

Title: Re: some question about the out document
Post by: ipsecog on January 6, 2009, 22:05

My guess is that you have added "Transmission coefficients" or "Transmission Eigenvalues" analysis options in VNL. When these are printed, using the nlPrint() function, the output looks like that since the object returned by the corresponding analysis functions are simple numpy arrays.

So in some sense the output is correct and proper (while not very pretty), and you actually asked for this information ;)

It would have been nice if the VNL-produced scripts also wrote some kind of headings or labels to the out file for those quantities. This is not done for any analysis quantities, however, it seems, since the nlPrint() function is supposed to take care of that internally for objects which it recognizes. But since it doesn't recognize these arrays as e.g. transmission eigenvalues (and how could it? it's just an array...), no heading is produced. The interplay between VNL and nlPrint() is thus not entirely well-designed in this respect.

Title: Re: some question about the out document
Post by: Anders Blom on January 6, 2009, 22:34

Indeed, most likely the culprit is a request for Transmission Eigenvalues, since the print-out in fact is to a list of two arrays, corresponding to the default k-points (0,0) and (0.5,0.5).

The comments made by ipsecog are quite valid; this is something to clean up in future editions of VNL. It has been put on the to-do list!

Title: Re: some question about the out document
Post by: Roc on January 7, 2009, 01:48

Thanks,

yeah, I just make the script by the VNL tool, I expect the VNL more perfect.

You've had a long day.You've had a long flight. Thanks again! ;D