Merge pull request #72 from cirKITers/noise

Noise

docs/ansaetze.md

@@ -26,7 +26,7 @@ class MyHardwareEfficient(Circuit):
         return None
 
     @staticmethod
-    def build(w: np.ndarray, n_qubits: int):
+    def build(w: np.ndarray, n_qubits: int, noise_params=None):
         w_idx = 0
         for q in range(n_qubits):
             qml.RY(w[w_idx], wires=q)
@@ -50,4 +50,47 @@ model = Model(
 )
 ```
 
-Checkout page ["Usage"](usage.md) on how to proceed from here.
+Checkout page ["Usage"](usage.md) on how to proceed from here.
+
+You might have noticed, that the `build` method takes an additional input `noise_params`, which we did not used so far.
+In general, all of the Ansatzes, that are implemented in this package allow this additional input which is a dictionary containing all the noise parameters of the circuit (here all with probability $0.0$):
+```python
+noise_params = {
+    "BitFlip": 0.0,
+    "PhaseFlip": 0.0,
+    "AmplitudeDamping": 0.0,
+    "PhaseDamping": 0.0,
+    "DepolarizingChannel": 0.0,
+}
+```
+
+Providing this optional input will apply the corresponding noise to the model where the Bit Flip, Phase Flip and Depolarizing Channel are applied after each gate and the Amplitude and Phase Damping are applied at the end of the circuit.
+To achieve this, we implement our own set of noisy gates, that build upon the Pennylane gates. To demonstrate this, let's extend our example above:
+```python
+from qml_essentials.ansaetze import Gates, Circuit
+
+class MyNoisyHardwareEfficient(Circuit):
+    @staticmethod
+    def n_params_per_layer(n_qubits: int) -> int:
+        return n_qubits * 3
+
+    @staticmethod
+    def get_control_indices(n_qubits: int) -> Optional[np.ndarray]:
+        return None
+
+    @staticmethod
+    def build(w: np.ndarray, n_qubits: int, noise_params=None):
+        w_idx = 0
+        for q in range(n_qubits):
+            Gates.RY(w[w_idx], wires=q, noise_params=noise_params)
+            w_idx += 1
+            Gates.RZ(w[w_idx], wires=q, noise_params=noise_params)
+            w_idx += 1
+
+        if n_qubits > 1:
+            for q in range(n_qubits - 1):
+                Gates.CZ(wires=[q, q + 1], noise_params=noise_params)
+```
+
+As you can see, we slightly modified the example, by importing the `Gates` class from `ansaetze` and by adding the `noise_params` input to each of the gates.
+When using a noisy circuit, make sure to run the model with the `density` execution type.

mkdocs.yml

@@ -4,14 +4,17 @@ nav:
   - setup.md
   - usage.md
   - Advanced:
-    - ansaetze.md
-    - coefficients.md
-    - entanglement.md
-    - expressibility.md
+      - ansaetze.md
+      - coefficients.md
+      - entanglement.md
+      - expressibility.md
   - references.md
 theme:
   name: material
   highlightjs: true
+  features:
+    - content.code.select
+    - content.code.copy
   palette:
     # Palette toggle for light mode
     - media: "(prefers-color-scheme: light)"
@@ -36,14 +39,21 @@ markdown_extensions:
   - markdown_include.include:
       base_path: .
   - toc:
-        permalink: "#"
-        baselevel: 1
-        separator: "_"
+      permalink: "#"
+      baselevel: 1
+      separator: "_"
   - pymdownx.emoji:
-      emoji_index: !!python/name:material.extensions.emoji.twemoji 
+      emoji_index: !!python/name:material.extensions.emoji.twemoji
       emoji_generator: !!python/name:material.extensions.emoji.to_svg
+  - pymdownx.highlight:
+      anchor_linenums: true
+      line_spans: __span
+      pygments_lang_class: true
+  - pymdownx.inlinehilite
+  - pymdownx.snippets
+  - pymdownx.superfences
 extra:
   social:
     - icon: fontawesome/brands/github
       link: https://github.com/cirKITers/qml-essentials
-      name: Github
+      name: Github