Implement Data-reuploading classifier in Qiskit Machine Learning

[ShivaniRajput11]

Description

Data re-uploading is a recently proposed idea of quantum neural network, which uses a quantum circuit with a series of data re-uploading and processing layers. Unlike the conventional quantum circuit of quantum neural network, it has multiple layers of re-uploading input data. In this project, we will implement the data re-uploading quantum neural network in Qiskit Machine Learning. The goal of this project is to write code and create a pull request

Details and comments

The work is done in QAMP23 (qiskit-advocate/qamp-spring-23#3)

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[OkuyanBoga]

The notebook needs to be updated for the unit tests:

• Check spelling
• Update outdated libraries

[edoaltamura]

Hi @ShivaniRajput11, are you still interested in finishing this PR? There are just a few things left to change to make it compatible with the latest Qiskit ML version:

• update from qiskit.utils import algorithm_globals
• run the spellchecker and add unknown words to .pylintdict

[ShivaniRajput11]

Hi @edoaltamura , yes I am still interested to finish this PR. I am working on it. Thanks.

[edoaltamura]

Note the recent changes in Qiskit ML that would require changes in this PR:

• from qiskit.utils import algorithm_globals: algorithm_globals is now hosted in Qiskit ML directly since the merge of Qiskit Algorithm last week.
• A new tutorial, number 13, has been merged in the main branch, so this tutorial should be renamed with the number 14.
• The V1 primitives are being deprecated across the Qiskit ecosystem and this change may affect SamplerQNN used here. Soon we will update Qiskit ML to reflect this upgrade, so this tutorial may need to be adjusted as well.

[woodsp-ibm]

Note: we ran into an issue on the main branch here a while back which resulted in us rolling back the main branch to an earlier commit and at the time main was renamed to oldmain as we created the new main branch from the earlier time. This PR is still targeting oldmain so in addition to whatever content updates were going to be done for this PR, if there is still any interest as there had been no activity in some months, it also needs to be done to the main branch that exists now. My take given how long this has been open and the branch change would be that perhaps this PR is best closed. A new PR using updated content from this, as per the above comments etc., can be opened if there is still interest.

Update: I edited the PR to retarget to main just in case. There is a conflict now. As I mentioned, if there is still interest, it may be better to apply your new content to a updated main and do a new PR.