Skip to content

linalg.Qr produces wrong (negative) auxiliary bond qnums for BlockUniTensor #761

@chiamin

Description

@chiamin

This is similar to #763.

linalg.Qr on a BlockUniTensor, T=QR, produces an auxiliary bond with wrong negative qnums when the bond directions are [OUT, IN, OUT] with rowrank=2. In the resulting R, no sector pair satisfies QN conservation, yet cytnx stores 2 nonzero blocks without raising an error.

I attached an example to demonstrate the bug.
cytnx_qr_wrong_qnums.py

I suggest that in linalg, any QN tensor needs to pass a QN check in debug mode before it is returned.

Environment: cytnx 1.0.0, Python 3.9, Linux

Metadata

Metadata

Assignees

No one assigned

    Labels

    bugSomething isn't working

    Type

    No type

    Projects

    No projects

    Milestone

    No milestone

    Relationships

    None yet

    Development

    No branches or pull requests

    Issue actions