How do the credit points work in IBM quantum experience?

Question

I am using Qiskit language, and I am working with IBM devices via Quantum Experience beta. How can I find how many credit points I have used and how much there are left till they fill back 24 hour's later? And for each backend, number of qubits and number of shots - how much credit points does the system require per experience with those data?

I would like to have a summary mentioning all is known about those credit points.

Answer 1

For experiments run on the simulator, ibmq_qasm_simulator, no credits are used. For all real devices available, running any experiment uses credits. The different amount of credits used depends on the amount of shots requested. Currently, there are only 4 options for amount of shots when running a circuit in the composer in the new IBM Q Experience beta. You can choose between 1, 1024, 4096, or 8192 shots. I believe if you choose 1 or 1024, it will require 3 credits. If you choose 4096 or 8192, it will require 5 credits.

I do not believe there is any indication on the beta as to how many credits you have/have used. You can view credits used on specific jobs by going to their respective results page, though.

The platform is still in beta, so these are features that can be added in the future as well.

Also, credits refresh upon the greater of the following: 24 hours or until your most recent job execution has completed.

Answer 2

I get a way to count the maximal, and the remaining credits. the maximal credits that was shown is 15, although I have made 10 runs and for each 3 credits till the program crushed due to lack of credits, so there is a Lack of coordination from what they write to what you can run for each 24 hours in practice.

there is packege that needed to be installed for each program, using your IBM account token and give you a dictionary type: {'remaining': x, 'promotional': 0, 'maxUserType': 15} when x is the remaining number of credits, the code that needed to be written is:

 ! pip install IBMQuantumExperience
from IBMQuantumExperience import IBMQuantumExperience
api = IBMQuantumExperience("YOUR TOKEN", config = {"url":'https://quantumexperience.ng.bluemix.net/api'}, verify=False)
api.get_my_credits()

In addition for what I saw there is no influence for the number of shots nor the number of qubits (till 5 because that I reached) influence on the number of credits the program consuming, this is an equal number usually equal to 3.