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@ChrisRackauckas
Created August 1, 2016 00:11
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_
_ _ _(_)_ | A fresh approach to technical computing
(_) | (_) (_) | Documentation: http://docs.julialang.org
_ _ _| |_ __ _ | Type "?help" for help.
| | | | | | |/ _` | |
| | |_| | | | (_| | | Version 0.4.6 (2016-06-19 17:16 UTC)
_/ |\__'_|_|_|\__'_| | Official http://julialang.org/ release
|__/ | x86_64-w64-mingw32
julia> using ODE
julia> using DifferentialEquations
julia> Pkg.update()
INFO: Updating METADATA...
INFO: Cloning cache of ODE from git://github.com/JuliaLang/ODE.jl.git
INFO: Updating ODE...
INFO: Updating DifferentialEquations...
INFO: Computing changes...
INFO: No packages to install, update or remove
julia> Pkg.rm("ODE")
INFO: No packages to install, update or remove
INFO: Package database updated
julia>
julia> using DifferentialEquations, Plots
julia>
julia> """Example problem with solution ``u(t)=u0*exp(α*t)``"""
"Example problem with solution ``u(t)=u0*exp(α*t)``"
julia> function vanDerPolExample(u0=[0;sqrt(3)])
f1(u,t) = (1-u[2].^2)*u[1] - u[2]
f2(u,t) = u[1]
f(u,t) = [f1(u,t);f2(u,t)]
return(ODEProblem(f,u0))
end
vanDerPolExample (generic function with 2 methods)
julia> prob = vanDerPolExample()
DifferentialEquations.ODEProblem(f,[0.0,1.7320508075688772],(anonymous function),false,2,(2,))
julia>
julia> δt = 1//2^(4) #The initial timestepping size. It will automatically assigjulia> δt = 1//2^(4) #The initial timestepping size. It will automatically assigned if not given.
1//16
julia> tspan = [0,20] # The timespan. This is the default if not given.
2-element Array{Int64,1}:
0
20
julia>
julia> sol =solve(prob::ODEProblem,tspan,δt=δt,alg=:ode45)
[DifferentialEquations.jl] Initializing backend: ODEJL
DifferentialEquations.ODESolution, 225 timesteps, final value [-0.4319028971751859,1.9224255971025037]
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