more solvers to register

src/attractors/solvers/euler.py

@@ -0,0 +1,9 @@
+from attractors.solvers.registry import SolverRegistry
+from attractors.type_defs import ParamVector, StateVector, SystemCallable
+
+
+@SolverRegistry.register("euler")
+def euler(
+    system_func: SystemCallable, state: StateVector, params: ParamVector, dt: float
+) -> StateVector:
+    return state + dt * system_func(state, params)

src/attractors/solvers/rk2.py

@@ -0,0 +1,11 @@
+from attractors.solvers.registry import SolverRegistry
+from attractors.type_defs import ParamVector, StateVector, SystemCallable
+
+
+@SolverRegistry.register("rk2")
+def rk2(
+    system_func: SystemCallable, state: StateVector, params: ParamVector, dt: float
+) -> StateVector:
+    k1 = system_func(state, params)
+    k2 = system_func(state + dt * k1, params)
+    return state + dt * (k1 + k2) / 2

src/attractors/solvers/rk3.py

@@ -0,0 +1,12 @@
+from attractors.solvers.registry import SolverRegistry
+from attractors.type_defs import ParamVector, StateVector, SystemCallable
+
+
+@SolverRegistry.register("rk3")
+def rk3(
+    system_func: SystemCallable, state: StateVector, params: ParamVector, dt: float
+) -> StateVector:
+    k1 = system_func(state, params)
+    k2 = system_func(state + dt * k1 / 2, params)
+    k3 = system_func(state - dt * k1 + 2 * dt * k2, params)
+    return state + dt * (k1 + 4 * k2 + k3) / 6

src/attractors/solvers/rk5.py

@@ -0,0 +1,19 @@
+from attractors.solvers.registry import SolverRegistry
+from attractors.type_defs import ParamVector, StateVector, SystemCallable
+
+
+@SolverRegistry.register("rk5")
+def rk5(
+    system_func: SystemCallable, state: StateVector, params: ParamVector, dt: float
+) -> StateVector:
+    k1 = system_func(state, params)
+    k2 = system_func(state + dt * k1 / 4, params)
+    k3 = system_func(state + dt * (k1 + k2) / 8, params)
+    k4 = system_func(state + dt * (k3 - k2 / 2 + k3), params)
+    k5 = system_func(state + dt * (-3 * k1 / 16 + 9 * k4 / 16), params)
+    k6 = system_func(
+        state
+        + dt * (-3 * k1 / 7 + 2 * k2 / 7 + 12 * k3 / 7 - 12 * k4 / 7 + 8 * k5 / 7),
+        params,
+    )
+    return state + dt * (7 * k1 + 32 * k3 + 12 * k4 + 32 * k5 + 7 * k6) / 90

src/attractors/solvers/stormer_verlet.py

@@ -0,0 +1,13 @@
+from attractors.solvers.registry import SolverRegistry
+from attractors.type_defs import ParamVector, StateVector, SystemCallable
+
+
+@SolverRegistry.register("stormer_verlet")
+def stormer_verlet(
+    system_func: SystemCallable, state: StateVector, params: ParamVector, dt: float
+) -> StateVector:
+    k1 = system_func(state, params)
+    half_state = state + 0.5 * dt * k1
+
+    k2 = system_func(half_state, params)
+    return state + dt * k2