# NonlinearSolve.jl - sol.stats returns nothing

**URL:** https://discourse.julialang.org/t/nonlinearsolve-jl-sol-stats-returns-nothing/109301
**Category:** General Usage
**Tags:** nonlinearsolve
**Created:** [January 26, 2024, 12:30pm UTC](https://discourse.julialang.org/t/nonlinearsolve-jl-sol-stats-returns-nothing/109301 "2024-01-26T12:30:22Z")
**Posts on this page:** 6
**Page:** 1

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### Author: ![jcass](https://avatars.discourse-cdn.com/v4/letter/j/7c8e57/32.png) [@jcass](https://discourse.julialang.org/u/jcass)
#### Post date: [January 26, 2024, 12:30pm UTC](https://discourse.julialang.org/t/nonlinearsolve-jl-sol-stats-returns-nothing/109301/1 "2024-01-26T12:30:22Z")

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I’m struggling to locate the solver stats in NonlinearSolve.jl. After running the basic example from the docs,

```julia
using NonlinearSolve

function f(u, p)
    u .* u .- p
end
u0 = [1.0, 1.0]
p = 2.0
prob = NonlinearProblem(f, u0, p)
sol = solve(prob, NewtonRaphson())

```

I’m finding that sol.stats is empty. Is there a keyword I need to set?

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### Author: ![ChrisRackauckas](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/chrisrackauckas/32/77_2.png) [@ChrisRackauckas](https://discourse.julialang.org/u/ChrisRackauckas)
#### Post date: [January 26, 2024, 12:44pm UTC](https://discourse.julialang.org/t/nonlinearsolve-jl-sol-stats-returns-nothing/109301/2 "2024-01-26T12:44:37Z")

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What version of NonlinearSolve and SciMLBase?

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### Author: ![jcass](https://avatars.discourse-cdn.com/v4/letter/j/7c8e57/32.png) [@jcass](https://discourse.julialang.org/u/jcass)
#### Post date: [January 26, 2024, 12:51pm UTC](https://discourse.julialang.org/t/nonlinearsolve-jl-sol-stats-returns-nothing/109301/3 "2024-01-26T12:51:17Z")

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SciMLBase v1.97.0  
NonlinearSolve v1.6.0

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### Author: ![ChrisRackauckas](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/chrisrackauckas/32/77_2.png) [@ChrisRackauckas](https://discourse.julialang.org/u/ChrisRackauckas)
#### Post date: [January 26, 2024, 12:58pm UTC](https://discourse.julialang.org/t/nonlinearsolve-jl-sol-stats-returns-nothing/109301/4 "2024-01-26T12:58:07Z")

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It was added in NonlinearSolve.jl v3.

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### Author: ![jcass](https://avatars.discourse-cdn.com/v4/letter/j/7c8e57/32.png) [@jcass](https://discourse.julialang.org/u/jcass)
#### Post date: [January 26, 2024, 1:10pm UTC](https://discourse.julialang.org/t/nonlinearsolve-jl-sol-stats-returns-nothing/109301/5 "2024-01-26T13:10:01Z")

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I see, thank you.

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### Author: ![Oscar\_Smith](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/oscar_smith/32/25343_2.png) [@Oscar\_Smith](https://discourse.julialang.org/u/Oscar_Smith)
#### Post date: [January 26, 2024, 2:03pm UTC](https://discourse.julialang.org/t/nonlinearsolve-jl-sol-stats-returns-nothing/109301/6 "2024-01-26T14:03:49Z")

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it’s also probably worth noting that prior to version 3, Nonlinear solve had a number of bugs that made it fail to converge or converge much slower than it should. As such, I strongly recommend upgrading.