# Problem in integrating Agents.jl and DifferentialEquations.jl
**URL:** https://discourse.julialang.org/t/problem-in-integrating-agents-jl-and-differentialequations-jl/114510
**Category:** Modelling & Simulations
**Tags:** question, agents, modelling
**Created:** [May 21, 2024, 1:36pm UTC](https://discourse.julialang.org/t/problem-in-integrating-agents-jl-and-differentialequations-jl/114510 "2024-05-21T13:36:39Z")
**Posts on this page:** 4
**Page:** 1
### Author:  [@Sahil\_Khan](https://discourse.julialang.org/u/Sahil_Khan)
#### Post date: [May 21, 2024, 1:36pm UTC](https://discourse.julialang.org/t/problem-in-integrating-agents-jl-and-differentialequations-jl/114510/1 "2024-05-21T13:36:39Z")
Hello, Everyone Im running this example from Agents.jl page – [example](https://docs.sciml.ai/Agents/v4.2/examples/diffeq/). I’m getting Error as shown below. It will be really helpful if someone can help me out here as its extracted directly from website. I will expect it to run without error. Did I miss something ?
Thank you 🙂
```julia
using Agents
using Distributions
using CairoMakie
using DifferentialEquations
using Random
mutable struct Fisher <: AbstractAgent
id::Int
competence::Int
yearly_catch::Float64
end
function agent_diffeq_step!(agent, model)
agent.yearly_catch = rand(model.rng, Poisson(agent.competence))
end
function model_diffeq_step!(model)
# We step 364 days with this call.
OrdinaryDiffEq.step!(model.i, 364.0, true)
# Only allow fishing if stocks are high enough
model.i.p[2] =
model.i.u[1] > model.min_threshold ? sum(a.yearly_catch for a in allagents(model)) :
0.0
# Notify the integrator that conditions may be altered
OrdinaryDiffEq.u_modified!(model.i, true)
# Then apply our catch modifier
OrdinaryDiffEq.step!(model.i, 1.0, true)
# Store yearly stock in the model for plotting
model.stock = model.i.u[1]
# And reset for the next year
model.i.p[2] = 0.0
OrdinaryDiffEq.u_modified!(model.i, true)
end
function initialise_diffeq(;
stock = 400.0, # Initial population of fish (lets move to an equilibrium position)
max_population = 500.0, # Maximum value of fish stock
min_threshold = 60.0, # Regulate fishing if population drops below this value
nagents = 50,
)
function fish_stock!(ds, s, p, t)
max_population, h = p
ds[1] = s[1] * (1 - (s[1] / max_population)) - h
end
prob = OrdinaryDiffEq.ODEProblem(fish_stock!, [stock], (0.0, Inf), [max_population, 0.0])
integrator = OrdinaryDiffEq.init(prob, OrdinaryDiffEq.Tsit5(); advance_to_tstop = true)
model = ABM(
Fisher;
properties = Dict(
:stock => stock,
:max_population => max_population,
:min_threshold => min_threshold,
:rng => MersenneTwister(1234),
:i => integrator, # The OrdinaryDiffEq integrator
),
)
for _ in 1:nagents
add_agent!(model, floor(rand(model.rng, truncated(LogNormal(), 1, 6))), 0.0)
end
model
end
modeldeq = initialise_diffeq()
_, resultsdeq = run!(modeldeq, agent_diffeq_step!, model_diffeq_step!, 20; mdata = [:stock])
```
Error:
```julia
ERROR: MethodError: no method matching should_we_collect(::Int64, ::StandardABM{…}, ::Bool)
Closest candidates are:
should_we_collect(::Any, ::Any, ::Any, ::Function)
@ Agents ~/.julia/packages/Agents/8JW8b/src/simulations/collect.jl:197
should_we_collect(::Any, ::Any, ::Any, ::AbstractVector)
@ Agents ~/.julia/packages/Agents/8JW8b/src/simulations/collect.jl:196
should_we_collect(::Any, ::Any, ::Any, ::Real)
@ Agents ~/.julia/packages/Agents/8JW8b/src/simulations/collect.jl:195
Stacktrace:
[1] run!(model::StandardABM{…}, agent_step!::typeof(agent_diffeq_step!), model_step!::typeof(model_diffeq_step!), n::Int64; when::Bool, when_model::Bool, mdata::Vector{…}, adata::Nothing, obtainer::Function, agents_first::Bool, showprogress::Bool, warn_deprecation::Bool)
@ Agents ~/.julia/packages/Agents/8JW8b/src/deprecations.jl:0
[2] top-level scope
@ Untitled-2:72
Some type information was truncated. Use `show(err)` to see complete types.
```
---
### Author:  [@Datseris](https://discourse.julialang.org/u/Datseris)
#### Post date: [May 21, 2024, 1:45pm UTC](https://discourse.julialang.org/t/problem-in-integrating-agents-jl-and-differentialequations-jl/114510/2 "2024-05-21T13:45:09Z")
> [@Sahil\_Khan](#):
>
> as its extracted directly from website
heh, sure, but which website?
Each version of Agents.jl has its own “website”. Have you checked that the version of Agents.jl you have installed matches the version in the “website” you copied the code from? That is one likely source of error.
It is best if you follow the advice here [Please read: make it easier to help you](https://discourse.julialang.org/t/please-read-make-it-easier-to-help-you/14757) which includes **reporting the package versions you are using** and **using the latest stable versions**.
---
### Author:  [@Datseris](https://discourse.julialang.org/u/Datseris)
#### Post date: [May 21, 2024, 1:46pm UTC](https://discourse.julialang.org/t/problem-in-integrating-agents-jl-and-differentialequations-jl/114510/3 "2024-05-21T13:46:00Z")
> [@Sahil\_Khan](#):
>
> `_, resultsdeq = run!(modeldeq, agent_diffeq_step!, model_diffeq_step!, 20; mdata = [:stock])`
From this code you are either using Agents.jl less than v6 or the example in the docs was not updated. THis is incorrect syntax in Agents.jl v6.
EDIT: the docs of v6 are properly updated: [DifferentialEquations.jl · Agents.jl](https://juliadynamics.github.io/Agents.jl/stable/examples/diffeq/)
---
### Author:  [@Sahil\_Khan](https://discourse.julialang.org/u/Sahil_Khan)
#### Post date: [May 21, 2024, 1:59pm UTC](https://discourse.julialang.org/t/problem-in-integrating-agents-jl-and-differentialequations-jl/114510/4 "2024-05-21T13:59:55Z")
Thank you for help. I thought website get updated after update in version. My bad 🥲