Description

Fixing a warning and an error revealed for julia 1.12-beta1. In particular:

1. Warning: Explicitly reference NDTensors for Tensor constructor from ITensors
2. Warning: Change Compat.get_num_threads to BLAS.get_num_threads since first one is deprecated.
3. Error in contract_threads: threadid goes from nthreads(:interactive) .+ 1:nthreads(:default) as reported in nthreads. The error was not spotted previously case the number of interactive threads was defaulted to 0, but now the default value is 1 as reported in the News. Note that this fixes the error, but threadid documentation suggest to don't use it for indexing arrays.

All the modifications should be still compatible with julia 1.11.5.

Fixes #1647

How Has This Been Tested?

Please add tests that verify your changes to a file in the test directory.

Please give a summary of the tests that you added to verify your changes.

• Test A
• Test B

Checklist:

• My code follows the style guidelines of this project. Please run using JuliaFormatter; format(".") in the base directory of the repository (~/.julia/dev/ITensors) to format your code according to our style guidelines.
• I have performed a self-review of my own code.
• I have commented my code, particularly in hard-to-understand areas.
• I have added tests that verify the behavior of the changes I made.
• I have made corresponding changes to the documentation.
• My changes generate no new warnings.
• Any dependent changes have been merged and published in downstream modules.