fix: use public api in diffusion_function

Author: oameye

CHANGELOG.md

@@ -1,3 +1,8 @@
+# v3.16
+
+- Support StochasticDiffEq v6.96+, where the diffusion function is no longer reachable via `integrator.g`. The extension now reads it from the `SDEProblem` (`prob.g`), which is a stable SciMLBase accessor that works across both old and new StochasticDiffEq versions.
+- Run the multiplicative and non-diagonal noise examples on the `CoupledSDEs` docs page so they actually integrate a trajectory.
+
 # v3.15
 
 - New function `named_variables(ds)` for getting the variable names of an MTK-generated dynamical system.

Project.toml

@@ -1,7 +1,7 @@
 name = "DynamicalSystemsBase"
 uuid = "6e36e845-645a-534a-86f2-f5d4aa5a06b4"
 repo = "https://github.com/JuliaDynamics/DynamicalSystemsBase.jl.git"
-version = "3.15.6"
+version = "3.16.0"
 
 [deps]
 ForwardDiff = "f6369f11-7733-5829-9624-2563aa707210"

docs/src/CoupledSDEs.md

@@ -84,6 +84,8 @@ function g!(du, u, p, t)
     return nothing
 end
 sde = CoupledSDEs(f!, rand(2)./10; g=g!)
+tr = trajectory(sde, 1.0)
+plot_trajectory(tr...)
 ```
 
 #### Non-diagonal noise
@@ -105,6 +107,8 @@ function g!(du, u, p, t)
 end
 diffeq = (alg = RKMilCommute(), reltol = 1e-3, abstol = 1e-3, dt=0.1)
 sde = CoupledSDEs(f!, rand(2)./10; g=g!, noise_prototype = zeros(2, 2), diffeq = diffeq)
+tr = trajectory(sde, 1.0)
+plot_trajectory(tr...)
 ```
 
 !!! warning

ext/src/classification.jl

@@ -50,7 +50,8 @@ function diffusion_function(g, IIP, noise_prototype)
 end
 
 function diffusion_function(ds::CoupledSDEs{IIP}) where {IIP}
-    return diffusion_function(ds.integ.g, IIP, referrenced_sciml_prob(ds).noise_rate_prototype)
+    prob = referrenced_sciml_prob(ds)
+    return diffusion_function(prob.g, IIP, prob.noise_rate_prototype)
 end
 
 """

test/stochastic.jl

@@ -104,7 +104,10 @@ end
         corr = CoupledSDEs(f, zeros(2); covariance = [1 0.3; 0.3 1])
         corr_alt = CoupledSDEs(f, zeros(2); g = g, noise_prototype = zeros(2, 2))
         @test corr.noise_type == corr_alt.noise_type
-        @test all(corr.integ.g(zeros(2), (), 0.0) .== corr_alt.integ.g(zeros(2), (), 0.0))
+        @test all(
+            DynamicalSystemsBase.referrenced_sciml_prob(corr).g(zeros(2), (), 0.0) .==
+            DynamicalSystemsBase.referrenced_sciml_prob(corr_alt).g(zeros(2), (), 0.0)
+        )
     end
 
     @testset "ArgumentError" begin