SRIW1 fails with a NoiseProcess

[bertini97]

Describe the bug 🐞

The following snippet

using StochasticDiffEq, DiffEqNoiseProcess

f(u, p, t) = -u
g(u, p, t) = 1.0

w = WienerProcess(0.0, 0.0)
prob = SDEProblem(f, g, 0.0, (0.0, 1.0), noise=w)
u = solve(prob, SRIW1())

produces

ERROR: MethodError: no method matching /(::Nothing, ::Float64)
The function `/` exists, but no method is defined for this combination of argument types.

Stacktrace:
  [1] _fastindex
    @ ~/.julia/packages/FastBroadcast/wfdTr/src/FastBroadcast.jl:37 [inlined]
  [2] _broadcasted
    @ ~/.julia/packages/FastBroadcast/wfdTr/src/FastBroadcast.jl:352 [inlined]
  [3] perform_step!(integrator::StochasticDiffEq.SDEIntegrator{…}, cache::StochasticDiffEq.SRIW1ConstantCache)
    @ StochasticDiffEq ~/.julia/packages/StochasticDiffEq/vo3vZ/src/perform_step/sri.jl:225
  [4] solve!(integrator::StochasticDiffEq.SDEIntegrator{…})
    @ StochasticDiffEq ~/.julia/packages/StochasticDiffEq/vo3vZ/src/solve.jl:634
  [5] __solve(prob::SDEProblem{…}, alg::SRIW1, timeseries::Vector{…}, ts::Vector{…}, ks::Nothing, recompile::Type{…}; kwargs::@Kwargs{})
    @ StochasticDiffEq ~/.julia/packages/StochasticDiffEq/vo3vZ/src/solve.jl:7
  [6] __solve (repeats 5 times)
    @ ~/.julia/packages/StochasticDiffEq/vo3vZ/src/solve.jl:1 [inlined]
  [7] #solve_call#44
    @ ~/.julia/packages/DiffEqBase/R2Vjs/src/solve.jl:634 [inlined]
  [8] solve_call
    @ ~/.julia/packages/DiffEqBase/R2Vjs/src/solve.jl:591 [inlined]
  [9] #solve_up#53
    @ ~/.julia/packages/DiffEqBase/R2Vjs/src/solve.jl:1122 [inlined]
 [10] solve_up
    @ ~/.julia/packages/DiffEqBase/R2Vjs/src/solve.jl:1101 [inlined]
 [11] #solve#51
    @ ~/.julia/packages/DiffEqBase/R2Vjs/src/solve.jl:1038 [inlined]
 [12] solve(prob::SDEProblem{…}, args::SRIW1)
    @ DiffEqBase ~/.julia/packages/DiffEqBase/R2Vjs/src/solve.jl:1028

which does not happen when the noise process is not provided or when then integrator is EM().

Environment:

• Output of using Pkg; Pkg.status()

Status `~/.julia/environments/v1.11/Project.toml`
  [13f3f980] CairoMakie v0.13.1
  [459566f4] DiffEqCallbacks v4.2.2
  [77a26b50] DiffEqNoiseProcess v5.24.1
  [2b0e0bc5] LanguageServer v4.5.1
  [bb33d45b] LuxCore v1.2.2
  [6f286f6a] MultivariateStats v0.10.3
  [1dea7af3] OrdinaryDiffEq v6.90.1
  [731186ca] RecursiveArrayTools v3.27.4
  [789caeaf] StochasticDiffEq v6.72.1
  [6fc51010] Surrogates v6.10.0
  [3a884ed6] UnPack v1.0.2
  [d49dbf32] WeightInitializers v1.1.1

• Output of versioninfo()

versioninfo()
Julia Version 1.11.3
Commit d63adeda50d (2025-01-21 19:42 UTC)
Build Info:
  Official https://julialang.org/ release
Platform Info:
  OS: Linux (x86_64-linux-gnu)
  CPU: 12 × Intel(R) Core(TM) i7-8700K CPU @ 3.70GHz
  WORD_SIZE: 64
  LLVM: libLLVM-16.0.6 (ORCJIT, skylake)
Threads: 1 default, 0 interactive, 1 GC (on 12 virtual cores)
Environment:
  LD_LIBRARY_PATH = 
  JULIA_EDITOR = code
  JULIA_NUM_THREADS =

Is it just me? Can someone reproduce?

[ChrisRackauckas]

using StochasticDiffEq, DiffEqNoiseProcess

f(u, p, t) = -u
g(u, p, t) = 1.0

w = WienerProcess(0.0, 0.0, 0.0)
prob = SDEProblem(f, g, 0.0, (0.0, 1.0), noise=w)
u = solve(prob, SRIW1())

You were just missing the Z process. It now prints a better error:

"Higher order solver requires extra Brownian process Z. Thus WienerProcess(t, W0)is insufficient, you must useWienerProcess(t, W0, Z0)whereZ is another Brownian process"