Add properties to get the line series and shunt currents

Fixes #99

The `Line` class gained two new properties:
1. `res_series_currents`: An array of currents in the series components of the line
2. `res_shunt_currents`: A 2-tuple of arrays of currents in the shunt components from
   each side of the line

The `ElectricalNetwork` now has a `res_lines` property that replaces `res_lines_losses`.
The new property contains all columns from `res_branches` in addition to the columns
`series_losses` and `series_current`. The columns `shunt_losses` and `total_losses` have
been removed but can be easily computed.
```py
df = en.res_lines
total_losses = df["power1"] + df["power2"]
shunt_losses = total_losses - df["series_losses"]
```

In addition, the shunt currents can be computed with:
```py
shunt_currents1 = df["current1"] - df["series_current"]
shunt_currents2 = df["series_current"] + df["current2"]
```

The detailed shunt losses/currents always remain accessible on the line element itself.

.vscode/settings.json

@@ -1,6 +1,10 @@
 {
-    // Jupyter
+    // Jupyter Notebook
     "jupyter.notebookFileRoot": "${workspaceFolder}",
+    "notebook.formatOnSave.enabled": true,
+    "notebook.codeActionsOnSave": {
+        "source.organizeImports.ruff": true,
+    },
 
     // Python
     "python.analysis.diagnosticSeverityOverrides": {

doc/Changelog.md

@@ -4,6 +4,10 @@
 
 **In development**
 
+* [GH99](https://github.com/RoseauTechnologies/Roseau_Load_Flow/issues/99) Add `Line.res_series_currents`
+  and `Line.res_shunt_currents` properties to get the currents in the series and shunt components
+  of lines. Also added `ElectricalNetwork.res_lines` that contains the series losses and currents
+  of all the lines in the network. The property `ElectricalNetwork.res_lines_losses` was removed.
 * [GH100](https://github.com/RoseauTechnologies/Roseau_Load_Flow/issues/100) Fix the `Yz` transformers
 * [PR97](https://github.com/RoseauTechnologies/Roseau_Load_Flow/pull/97) Add the model section to the documentation
 * [PR96](https://github.com/RoseauTechnologies/Roseau_Load_Flow/pull/96)

doc/models/Line/ShuntLine.md

@@ -150,12 +150,33 @@ en.res_branches[["current2"]].transform([np.abs, ft.partial(np.angle, deg=True)]
 # | ('line', 'c') |                5.68434e-14 |                  0      |
 # | ('line', 'n') |               20.6273      |                -12.625  |
 
-# The losses of the line can also be accessed. One can remark that there are shunt losses
-en.res_lines_losses
-# |               |          'series_losses' |       'shunt_losses' | 'total_losses'    |
-# |:--------------|-------------------------:|---------------------:|------------------:|
-# | ('line', 'a') | 171.841+57.2802j         | -1.59017-26.6385j    | 170.251+ 30.6417j |
-# | ('line', 'b') |  38.1291+12.7097j        | 1.01834-28.5657j     | 39.1474 -15.856j  |
-# | ('line', 'c') |  0.00107497+0.000358324j | 3.69511-27.4104j     | 3.69618-27.41j    |
-# | ('line', 'n') |  127.574  +42.5246j      | 0.0351686+0.0139828j | 127.609+42.5385j  |
+# The currents in the series components of the line
+en.res_lines[["series_current"]].transform([np.abs, ft.partial(np.angle, deg=True)])
+# |               |   ('series_current', 'absolute') |   ('series_current', 'angle') |
+# |:--------------|---------------------------------:|------------------------------:|
+# | ('line', 'a') |                       23.9333    |                       15.5496 |
+# | ('line', 'b') |                       11.2737    |                     -104.796  |
+# | ('line', 'c') |                        0.0598601 |                     -157.579  |
+# | ('line', 'n') |                       20.6215    |                      167.376  |
+
+# The losses of the series components of line can also be accessed
+en.res_lines[["series_losses"]].transform([np.real, np.imag])
+# |               |   ('series_losses', 'real') |   ('series_losses', 'imag') |
+# |:--------------|----------------------------:|----------------------------:|
+# | ('line', 'a') |                171.841      |                57.2802      |
+# | ('line', 'b') |                 38.1291     |                12.7097      |
+# | ('line', 'c') |                  0.00107497 |                 0.000358324 |
+# | ('line', 'n') |                127.574      |                42.5246      |
+
+# The shunt losses can be computed. Notice that the shunt losses are not null for the shunt line.
+res_lines = en.res_lines
+total_losses = res_lines["power1"] + res_lines["power2"]  # total = series + shunt
+shunt_losses = total_losses - res_lines["series_losses"]
+shunt_losses.to_frame("shunt_losses").transform([np.real, np.imag])
+# |               |   ('shunt_losses', 'real') |   ('shunt_losses', 'imag') |
+# |:--------------|---------------------------:|---------------------------:|
+# | ('line', 'a') |                 -1.59017   |                -26.6385    |
+# | ('line', 'b') |                  1.01834   |                -28.5657    |
+# | ('line', 'c') |                  3.69511   |                -27.4104    |
+# | ('line', 'n') |                  0.0351686 |                  0.0139828 |
 ```

doc/models/Line/SimplifiedLine.md

@@ -96,14 +96,30 @@ en.res_branches[["current2"]].transform([np.abs, ft.partial(np.angle, deg=True)]
 # | ('line', 'c') |                     0      |                  0      |
 # | ('line', 'n') |                    20.628  |                -11.5242 |
 
-# The two currents are equal in magnitude and opposite in phase, as expected
+# The currents in the series components of the line
+en.res_lines[["series_current"]].transform([np.abs, ft.partial(np.angle, deg=True)])
+# |               |   ('series_current', 'absolute') |   ('series_current', 'angle') |
+# |:--------------|---------------------------------:|------------------------------:|
+# | ('line', 'a') |                          24.1958 |                       16.4456 |
+# | ('line', 'b') |                          11.3722 |                     -105.263  |
+# | ('line', 'c') |                           0      |                        0      |
+# | ('line', 'n') |                          20.628  |                      168.476  |
+
+# All currents are equal in magnitude for a simplified lines as no current escapes to the ground.
+# The current from bus 2 has an opposite direction to the current from bus 1 as expected.
 
 # The losses of the line can also be accessed. One can remark that there are no shunt losses
-en.res_lines_losses
-# |               |   'series_losses'      | 'shunt_losses' |  'total_losses'       |
-# |:--------------|-----------------------:|---------------:|----------------------:|
-# | ('line', 'a') | 204.904 -2.66329e-15   |             0j | 204.904 -2.66329e-15  |
-# | ('line', 'b') |  45.2646 -8.96306e-16  |             0j |  45.2646 -8.96306e-16 |
-# | ('line', 'c') |   0j                   |             0j |   0j                  |
-# | ('line', 'n') | 148.93 + 6.11606e-15   |             0j | 148.93 + 6.11606e-15  |
+en.res_lines[["series_losses"]].transform([np.real, np.imag])
+# |               |   ('series_losses', 'real') |   ('series_losses', 'imag') |
+# |:--------------|----------------------------:|----------------------------:|
+# | ('line', 'a') |                    204.904  |                -2.66329e-15 |
+# | ('line', 'b') |                     45.2646 |                -8.96306e-16 |
+# | ('line', 'c') |                      0      |                 0           |
+# | ('line', 'n') |                    148.93   |                 7.62657e-16 |
+
+# With a simplified model, all the losses are caused by the series impedance of the line
+res_lines = en.res_lines
+total_losses = res_lines["power1"] + res_lines["power2"]  # total = series + shunt
+np.allclose(total_losses, res_lines["series_losses"])
+# True
 ```