Deprecate python 3.9 support (#5052)

* Remove python 3.9

* Pre-commit changes

* pre-commit

* Update changelog

* Fix some docs

* Update src/pybamm/discretisations/discretisation.py

Author: kratman

.github/workflows/run_periodic_tests.yml

@@ -31,7 +31,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [ ubuntu-latest, macos-13, macos-14, windows-latest ]
-        python-version: [ "3.9", "3.10", "3.11", "3.12" ]
+        python-version: ["3.10", "3.11", "3.12"]
     name: Tests (${{ matrix.os }} / Python ${{ matrix.python-version }})
 
     steps:

.github/workflows/test_on_push.yml

@@ -49,7 +49,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [ubuntu-latest, macos-13, macos-14, windows-latest]
-        python-version: ["3.9", "3.10", "3.11", "3.12"]
+        python-version: ["3.10", "3.11", "3.12"]
     name: Tests (${{ matrix.os }} / Python ${{ matrix.python-version }})
 
     steps:

CHANGELOG.md

@@ -4,15 +4,14 @@
 
 - Generalise `pybamm.DiscreteTimeSum` to allow it to be embedded in other expressions ([#5044](https://github.com/pybamm-team/PyBaMM/pull/5044))
 
-## Optimizations
-
 ## Bug fixes
 
 - Converts sensitivities to numpy objects, fixing bug in `DiscreteTimeSum` sensitivity calculation ([#5037](https://github.com/pybamm-team/PyBaMM/pull/5037))
 
-
 ## Breaking changes
 
+- Removed support for Python 3.9 ([#5052](https://github.com/pybamm-team/PyBaMM/pull/5052))
+
 # [v25.6.0](https://github.com/pybamm-team/PyBaMM/tree/v25.6.0) - 2025-05-27
 
 ## Features

docs/source/examples/notebooks/batch_study.ipynb

@@ -200,7 +200,7 @@
     "# changing the value of \"Current function [A]\" in all the parameter values present in the\n",
     "# parameter_values dictionary\n",
     "for _, v, current_value in zip(\n",
-    "    parameter_values.keys(), parameter_values.values(), current_values\n",
+    "    parameter_values.keys(), parameter_values.values(), current_values, strict=False\n",
     "):\n",
     "    v[\"Current function [A]\"] = current_value\n",
     "\n",
@@ -506,7 +506,7 @@
     "\n",
     "# updating the value of \"SEI open-circuit potential [V]\" in all the dictionary items\n",
     "for _, v, sei_oc_v in zip(\n",
-    "    parameter_values.keys(), parameter_values.values(), sei_oc_v_values\n",
+    "    parameter_values.keys(), parameter_values.values(), sei_oc_v_values, strict=False\n",
     "):\n",
     "    v.update(\n",
     "        {\"SEI open-circuit potential [V]\": sei_oc_v},\n",

docs/source/examples/notebooks/models/graded-electrodes.ipynb

@@ -105,7 +105,7 @@
     "\n",
     "experiment = pybamm.Experiment([\"Discharge at 3C until 2.5 V\"])\n",
     "\n",
-    "for eps_n, eps_p in zip(eps_ns, eps_ps):\n",
+    "for eps_n, eps_p in zip(eps_ns, eps_ps, strict=False):\n",
     "    parameter_values[\"Negative electrode porosity\"] = eps_n\n",
     "    parameter_values[\"Positive electrode porosity\"] = eps_p\n",
     "    sim = pybamm.Simulation(\n",

docs/source/examples/notebooks/models/lithium-plating-composite.ipynb

@@ -498,7 +498,7 @@
     "\n",
     "    fig, axs = plt.subplots(2, 2, figsize=(13, 9))\n",
     "    ax2 = axs[1, 1].twinx()  # Create a secondary y-axis\n",
-    "    for (C_rate, sim), color in zip(sims.items(), colors):\n",
+    "    for (C_rate, sim), color in zip(sims.items(), colors, strict=False):\n",
     "        # Isolate final equilibration phase\n",
     "        sol = sim.solution.cycles[0].steps[2]\n",
     "\n",
@@ -509,7 +509,7 @@
     "        axs[0, 0].plot(t, V, color=color, linestyle=\"solid\", label=C_rate)\n",
     "\n",
     "        # Currents\n",
-    "        for current, ls in zip(currents, linestyles):\n",
+    "        for current, ls in zip(currents, linestyles, strict=False):\n",
     "            j = sol[current].entries\n",
     "            axs[0, 1].plot(t, j, color=color, linestyle=ls)\n",
     "\n",

docs/source/examples/notebooks/models/lithium-plating.ipynb

@@ -194,7 +194,7 @@
     "    import matplotlib.pyplot as plt\n",
     "\n",
     "    fig, axs = plt.subplots(2, 2, figsize=(13, 9))\n",
-    "    for (C_rate, sim), color in zip(sims.items(), colors):\n",
+    "    for (C_rate, sim), color in zip(sims.items(), colors, strict=False):\n",
     "        # Isolate final equilibration phase\n",
     "        sol = sim.solution.cycles[0].steps[2]\n",
     "\n",
@@ -205,7 +205,7 @@
     "        axs[0, 0].plot(t, V, color=color, linestyle=\"solid\", label=C_rate)\n",
     "\n",
     "        # Currents\n",
-    "        for current, ls in zip(currents, linestyles):\n",
+    "        for current, ls in zip(currents, linestyles, strict=False):\n",
     "            j = sol[current].entries\n",
     "            axs[0, 1].plot(t, j, color=color, linestyle=ls)\n",
     "\n",

docs/source/examples/notebooks/models/sodium-ion.ipynb

@@ -120,7 +120,7 @@
    "source": [
     "import matplotlib.pyplot as plt\n",
     "\n",
-    "for solution, C_rate in zip(solutions, C_rates):\n",
+    "for solution, C_rate in zip(solutions, C_rates, strict=False):\n",
     "    capacity = [i * 1000 for i in solution[\"Discharge capacity [A.h]\"].entries]\n",
     "    voltage = solution[\"Voltage [V]\"].entries\n",
     "    plt.plot(capacity, voltage, label=f\"{(12 * C_rate)} A.m-2\")\n",

docs/source/examples/notebooks/models/thermal-models.ipynb

@@ -448,7 +448,7 @@
     "params = [full_params, lumped_params]\n",
     "# loop over the models and solve\n",
     "sols = []\n",
-    "for model, param in zip(models, params):\n",
+    "for model, param in zip(models, params, strict=False):\n",
     "    param[\"Current function [A]\"] = 3 * 0.68\n",
     "    sim = pybamm.Simulation(model, parameter_values=param)\n",
     "    sim.solve([0, 3600])\n",
@@ -552,7 +552,7 @@
    "source": [
     "params = [lumped_params, lumped_params_contact_resistance]\n",
     "sols = []\n",
-    "for model, param in zip(models, params):\n",
+    "for model, param in zip(models, params, strict=False):\n",
     "    sim = pybamm.Simulation(model, parameter_values=param)\n",
     "    sim.solve([0, 3600])\n",
     "    sols.append(sim.solution)"

docs/source/examples/notebooks/solvers/idaklu-jax-interface.ipynb

@@ -8,7 +8,7 @@
    "source": [
     "# IDAKLU-JAX interface\n",
     "\n",
-    "The IDAKLU-JAX interface requires that PyBaMM is installed with the [optional JAX solver enabled](https://docs.pybamm.org/en/stable/source/user_guide/installation/gnu-linux-mac.html#optional-jaxsolver) (`pip install pybamm[jax]`) and requires at least Python 3.9.\n",
+    "The IDAKLU-JAX interface requires that PyBaMM is installed with the [optional JAX solver enabled](https://docs.pybamm.org/en/stable/source/user_guide/installation/gnu-linux-mac.html#optional-jaxsolver) (`pip install pybamm[jax]`) and requires at least Python 3.10.\n",
     "\n",
     "PyBaMM provides two mechanisms to interface battery models with JAX. The first (JaxSolver) implements PyBaMM models directly in native JAX, and as such provides the greatest flexibility. However, these models can be very slow to compile, especially during their initial run, and can require large amounts of memory.\n",
     "\n",