Create `subdistribution()` function for MeasurementOutcomeDistribution

[AthenaCaesura]

Our scientists often make use of more qubits than they measure at the end of their experiments (e.g. ancilla qubits). Currently, our MeasurementOutcomeDistributions (defined here) can become difficult to read if there are many other qubits that we really should just ignore.

We should solve this issue by adding a function subdistribution() which takes a list of qubit indices and returns the same MeasurementOutcomeDistribution with only the provided qubits. That is, we should sum all the counts associated with each outcome of the provided qubits.

@AthenaCaesura has written some ad-hoc code to modify a dictionary of counts to exclude qubits, but it would be nice if we incorporated this into a function which is callable from the distribution itself and returns a MeasurementOutcomeDistribution.

Deliverables:

• [ ] Write subdistribution function as described above.
• [ ] Write tests for subdistribution including cases where:
  1. All the qubits remain active
  2. Input list contains qubit indices not present in the original distribution.

Affected repo: orquestra-quantum

[fred5825]

@AthenaCaesura Hi would like to give this a try if possible

[mstechly]

@fred5825 Feel free!

[fred5825]

Awesome thank you @mstechly I was wondering if you would be at the unitaryhack office hours. So we could discuss more, I am new to hackathons and opensource, I don't know my way around much.

[AthenaCaesura]

I would love to be at the UH office hours! But I can't seem to find the schedule.... the UH FAQ says they should be on the discord, but I can't seem to find them. At the very least if you want to chat 1:1 I'm sure I can find some time. 😄

[fred5825]

@AthenaCaesura Awesome thank you please let me know what time you are available to chat. Also to find the UH office hours is on the top of the discord page in events.

[mstechly]

@fred5825 I added some timeslots for office hours, but it seems the website didn't auto-update yet. Keep an eye on it though!

[fred5825]

@mstechly Awesome thank you and just to confirm, you mean the UH website right?

[mstechly]

@fred5825 I mean here: https://unitary.fund/talks.html

[fred5825]

Thank you I will check it out.

[Renaud2002]

Hi @mstechly I was wondering if you could add this account to the issue the acount: fred5825 is my school account, I wanted to make the changes using me personal account. At the moment I can't commit my code because it says permission denied. Very sorry for the inconvenience.

[mstechly]

@Renaud2002 @fred5825 I can't give you write access to the repository, as you're not Zapata employee, but this is not a really problem. You can fork the repo and make a pull request from there, just follow the procedure described here :)

[fred5825]

Yes of course I tried push it to my fork but this is the error that i encounter, I don't know why it says this

[fred5825]

@mstechly I think I know why the issue is happening I think I might have maybe clone the actual repository instead of my fork.

[fred5825]

@mstechly That was in fact the issue I am very sorry for the inconvenience, the pull request has been created.

[mstechly]

@fred5825 No problem! I'll take a look tomorrow!

[fred5825]

@mstechly Awesome thank you.