Separate State Preparation from Initialize (#7666)

* Split initialize and stateprep first attempt

* Tidied up code and added some tests

* ✨ lint ✨

* Tidied up code

* Removed unnecessary file

* Formatted docstrings

* Formatted docstrings again

* ✨ lint again ✨

* Fixed some docs bugs and added tests

* Update docs and lint

* docs fix

* Change StatePrep to a Gate and update tests

* Fixed tests and docs

* ✨ lint ✨

* Fixed test

* Add parmas getter and setter

* Fix stateprep inverse

* Fix merge issues

* Fix stateprep inverse

* Fix broadcast_arg error

* ✨ Lint! ✨

* Updated based on PR comments

* ✨ Lint ✨

* Update qiskit/extensions/quantum_initializer/state_preparation.py

Co-authored-by: Julien Gacon <gaconju@gmail.com>

* Moved stateprep to circuit library

* Adjust label logic

* Update qiskit/circuit/library/data_preparation/state_preparation.py

Co-authored-by: Julien Gacon <gaconju@gmail.com>

* Update qiskit/circuit/library/data_preparation/state_preparation.py

Co-authored-by: Julien Gacon <gaconju@gmail.com>

* Update qiskit/circuit/library/data_preparation/state_preparation.py

Co-authored-by: Julien Gacon <gaconju@gmail.com>

* Fixed docstrings and tests

* Update qiskit/circuit/library/data_preparation/state_preparation.py

Co-authored-by: Julien Gacon <gaconju@gmail.com>

* Added repeat test

* Added test and reno

* Fix label issue

* Fixed docstrings

* ✨ Lint! ✨

Co-authored-by: Julien Gacon <gaconju@gmail.com>
Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

qiskit/circuit/library/__init__.py

@@ -262,6 +262,7 @@
    PauliFeatureMap
    ZFeatureMap
    ZZFeatureMap
+   StatePreparation
 
 NCT (Not-CNOT-Toffoli) template circuits
 ========================================
@@ -416,7 +417,7 @@
     ExcitationPreserving,
     QAOAAnsatz,
 )
-from .data_preparation import PauliFeatureMap, ZFeatureMap, ZZFeatureMap
+from .data_preparation import PauliFeatureMap, ZFeatureMap, ZZFeatureMap, StatePreparation
 from .quantum_volume import QuantumVolume
 from .fourier_checking import FourierChecking
 from .graph_state import GraphState

qiskit/circuit/library/data_preparation/__init__.py

@@ -41,9 +41,6 @@
 from .pauli_feature_map import PauliFeatureMap
 from .z_feature_map import ZFeatureMap
 from .zz_feature_map import ZZFeatureMap
+from .state_preparation import StatePreparation
 
-__all__ = [
-    "PauliFeatureMap",
-    "ZFeatureMap",
-    "ZZFeatureMap",
-]
+__all__ = ["PauliFeatureMap", "ZFeatureMap", "ZZFeatureMap", "StatePreparation"]