added qiskit api docs

doc/requirements.txt

@@ -9,3 +9,4 @@ numpydoc==1.4.0
 matplotlib==3.5.2
 docutils==0.17.1
 sphinxcontrib-bibtex==2.4.2
+qiskit==0.37.2

doc/source/apidoc.rst

@@ -33,3 +33,16 @@ Simulation based on the master equation.
    qutip_qip.compiler
    qutip_qip.pulse
    qutip_qip.noise
+
+Qiskit Circuit Simulation
+--------------------------
+Simulation of qiskit circuits based on qutip_qip backends.
+
+.. autosummary::
+   :toctree: apidoc/
+   :template: autosummary/module.rst
+
+   qutip_qip.qiskit.backend
+   qutip_qip.qiskit.converter
+   qutip_qip.qiskit.provider
+   qutip_qip.qiskit.job

doc/source/apidoc/qutip_qip.qiskit.rst

@@ -0,0 +1,56 @@
+:orphan:
+
+qutip\_qip.qiskit.backend
+===========================
+
+.. automodule:: qutip_qip.qiskit.backend
+   :members:
+   :show-inheritance:
+
+   .. rubric:: Classes
+
+   .. autosummary::
+
+      QiskitSimulatorBase
+      QiskitCircuitSimulator       
+      QiskitPulseSimulator     
+
+qutip\_qip.qiskit.converter
+==============================
+
+.. automodule:: qutip_qip.qiskit.converter
+   :members:
+   :show-inheritance:
+
+   .. rubric:: Methods
+
+   .. autosummary::
+
+      convert_qiskit_circuit       
+
+qutip\_qip.qiskit.provider
+===========================
+
+.. automodule:: qutip_qip.qiskit.provider
+   :members:
+   :show-inheritance:
+
+   .. rubric:: Classes
+
+   .. autosummary::
+
+      Provider       
+
+qutip\_qip.qiskit.job
+===========================
+
+.. automodule:: qutip_qip.qiskit.job
+   :members:
+   :show-inheritance:
+
+   .. rubric:: Classes
+
+   .. autosummary::
+
+      Job
+

doc/source/qip-qiskit.rst

@@ -1,6 +1,10 @@
-******************************
-Qiskit
-******************************
+.. _qip_qiskit:
+
+**********************************
+`qutip-qip` as a Qiskit backend
+**********************************
+
+This submodule was implemented by `Shreyas Pradhan <shpradhan12@gmail.com>`_ as part of Google Summer of Code 2022.
 
 Overview
 ===============
@@ -42,8 +46,10 @@ Let's run this on the :class:`.QiskitCircuitSimulator` backend:
     job = backend.run(circ)
     result = job.result()
     
->>> from qiskit.visualization import plot_histogram
->>> plot_histogram(result.get_counts())
+.. code-block:: 
+
+    from qiskit.visualization import plot_histogram
+    >>> plot_histogram(result.get_counts())
 
 .. image:: /figures/qiskit-gate-level-plot.png
     :alt: probabilities plot 
@@ -58,7 +64,7 @@ While using a pulse processor, we define the circuit without measurements:
     pulse_circ.h(0)
     pulse_circ.h(1)
 
-To use the :class:`.QiskitPulseSimulator` backend, we need to define the processor on which we want to run the circuit:
+To use the :class:`.QiskitPulseSimulator` backend, we need to define the processor on which we want to run the circuit. This includes defining the pulse processor model with all the required parameters including noise. 
 
 .. code-block::
 
@@ -75,7 +81,9 @@ Now that we defined our processor (:class:`.LinearSpinChain` in this case), we c
     pulse_job = pulse_backend.run(pulse_circ)
     pulse_result = pulse_job.result()
 
->>> plot_histogram(pulse_result.get_counts())
+.. code-block::
+
+    >>> plot_histogram(pulse_result.get_counts())
 
 .. image:: /figures/qiskit-pulse-level-plot.png
     :alt: probabilities plot
@@ -95,6 +103,8 @@ Qiskit's interface allows us to provide some options like ``shots`` while runnin
 (Only available for :class:`.QiskitCircuitSimulator`)
 ``allow_custom_gate``, when set to ``False``, does not allowing simulating circuits that have user-defined gates; it will throw an error in that case. By default, it is set to ``True``, in which case, the backend will simulate a user-defined gate by computing its unitary matrix.
 
+  .. note::
+
     The pulse backend does not allow simulation with user-defined gates.
 
 An example demonstrating configuring options:

src/qutip_qip/device/cavityqed.py

@@ -103,21 +103,21 @@ def sx_ops(self):
         """
         list: A list of sigmax Hamiltonians for each qubit.
         """
-        return self.ctrls[0: self.num_qubits]
+        return self.ctrls[0 : self.num_qubits]
 
     @property
     def sz_ops(self):
         """
         list: A list of sigmaz Hamiltonians for each qubit.
         """
-        return self.ctrls[self.num_qubits: 2 * self.num_qubits]
+        return self.ctrls[self.num_qubits : 2 * self.num_qubits]
 
     @property
     def cavityqubit_ops(self):
         """
         list: A list of interacting Hamiltonians between cavity and each qubit.
         """
-        return self.ctrls[2 * self.num_qubits: 3 * self.num_qubits]
+        return self.ctrls[2 * self.num_qubits : 3 * self.num_qubits]
 
     @property
     def sx_u(self):
@@ -127,15 +127,15 @@ def sx_u(self):
     @property
     def sz_u(self):
         """array-like: Pulse matrix for sigmaz Hamiltonians."""
-        return self.coeffs[self.num_qubits: 2 * self.num_qubits]
+        return self.coeffs[self.num_qubits : 2 * self.num_qubits]
 
     @property
     def g_u(self):
         """
         array-like: Pulse matrix for interacting Hamiltonians
         between cavity and each qubit.
         """
-        return self.coeffs[2 * self.num_qubits: 3 * self.num_qubits]
+        return self.coeffs[2 * self.num_qubits : 3 * self.num_qubits]
 
     def eliminate_auxillary_modes(self, U):
         """

src/qutip_qip/device/modelprocessor.py

@@ -164,7 +164,7 @@ def pulse_matrix(self, dt=0.01):
             t_idx_len = int(np.floor(dt_list[n] / dt))
             mm = 0
             for m in range(len(ctrls)):
-                u[mm, t_start: (t_start + t_idx_len)] = (
+                u[mm, t_start : (t_start + t_idx_len)] = (
                     np.ones(t_idx_len) * coeffs[n, m]
                 )
                 mm += 1

src/qutip_qip/qiskit/backend.py

@@ -1,3 +1,5 @@
+"""Backends for simulating qiskit circuits."""
+
 import numpy as np
 import uuid
 import random

src/qutip_qip/qiskit/converter.py

@@ -1,3 +1,5 @@
+"""Conversion of circuits from qiskit to qutip_qip."""
+
 from qutip_qip.circuit import QubitCircuit
 from qiskit.quantum_info import Operator
 import numpy as np
@@ -94,7 +96,7 @@ def convert_qiskit_circuit(
     qiskit_circuit : QuantumCircuit
         QuantumCircuit to be converted to QubitCircuit.
 
-    all_custom_gate : bool
+    allow_custom_gate : bool
         If False, this function will raise an error if
         gate conversion is done using a custom gate's
         unitary matrix.

src/qutip_qip/qiskit/job.py

@@ -1,3 +1,5 @@
+"""Class for a running job."""
+
 from qiskit.providers import JobV1, JobStatus
 from qiskit.result import Result
 
@@ -8,14 +10,14 @@ class Job(JobV1):
 
     Parameters
     ----------
-    backend : QiskitCircuitSimulator
+    backend : :class:`.QiskitCircuitSimulator`
         The backend used to simulate a
         circuit in the job.
 
     job_id : str
         Unique ID identifying a job.
 
-    result : qiskit.result.Result
+    result : :class:`qiskit.result.Result`
         The result of a simulation run.
     """
 

src/qutip_qip/qiskit/provider.py

@@ -1,3 +1,5 @@
+"""Provider for the simulator backends."""
+
 from qiskit.providers.provider import ProviderV1
 from .backend import QiskitCircuitSimulator, QiskitPulseSimulator