quantum-computing

Several katas could have better error messaging:

• Superposition : the test harness could log the actual state of the system after prep vs the expected state before asserting that they are the same (the change would add state prep and logging using DumpMachine to AssertEqualOnZeroState)
• BasicGates : a similar improvement, but a bit more extra code to write a unified test wrapper

Here are some examples:

• Root README is missing machine learning category of samples
• README in algorithms is missing repeat-until-success and sudoku-grover
• [README in diagnostics](https://github.com/microsoft/Quantum/blob/main/samples/diagnostics/RE

Information

• Qiskit Terra version: latest
• Python version:
• Operating system:

What is the current behavior?

qc = QuantumCircuit(1)
qc.x(0)
qc.measure_all()

trans_qc = transpile(qc, backend, instruction_duration

There's quite a wall of boilerplate code to go along with the cirq.google tutorials to handle the various cases: [simulator, engine] x [colab, ipython, other] x [explicitly set, environment variable].

We should factor this out into a library function that you can call to do auth and get a device and sampler (and maybe an engine? we don't have a simulator analog of engine)

To get this codebase up to standard, we need to add type hints. At the very least, perhaps we should start insisting that all new code has type hints added, but moreover we need to add typing to the code that currently exists.

This is a pretty large project, but luckily it can be done incrementally - I believe at this point it's a stretch goal for v1, if anyone wants to help it would be much ap

Is your feature request related to a problem? Please describe.
I would like to check the behavior of the parameter index in the function QubitCircuit.add_gate()

In qutip.qip.QubitCircuit.add_gate(), there is a optional list type attribute called index.
This seems to be used to insert gates in the middle of the gate list (qutip.qip.QubitCircuit.gates).
The corresponding code is

For example, pylint would have caught ProjectQ-Framework/ProjectQ#19 via an undefined variable warning.

Currently, the Bosonic backend does not support the MeasureFock and MeasureThreshold measurement operations. It would be great to add support for these two operations to the Bosonic backend.

This would entail writing functions to calculate the different probabilities up to a given cutoff, using numpy to sample from this distribution and writing update rules for updating the post measurement

Describe the issue
In this section of textbook clearly two simulation methods are used Statevector and Qasm . But there is a problem in content as these simulation method are part of aer_simulator. One can clearly see that only aer_simulator is defined in code but the statevector and qasm are used in content.

Describe what you expect to see
I think one should fix the content and

Describe the bug
If I provide Partitioned an array of length N and partition sizes of total length N, the return contains an extra partition of length 0 in the end. This makes it inconvenient to use: if I want to split an array into K parts of equal length ([example](https://github.com/microsoft/Quantum

It is hard to debug these hash table monstrosities without some visualization. Maybe we can visualize them with a Hasse diagram.