# Calculating first integral **URL:** \ **Category:** Modelling & Simulations\ **Created:** [July 6, 2023, 3:42pm UTC](https://discourse.julialang.org/t/calculating-first-integral/101267 "2023-07-06T15:42:09Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![Sergey\_Novak](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/sergey_novak/32/37716_2.png) [@Sergey\_Novak](https://discourse.julialang.org/u/Sergey_Novak)\ **Post date:** [July 6, 2023, 3:42pm UTC](https://discourse.julialang.org/t/calculating-first-integral/101267/1 "2023-07-06T15:42:09Z")
Hello! I have an ODE system of 7 equations, and calculating the first integral analytically is a bit difficult for me. Are there packages for calculating the first integral of the ODE system? Thank you for help ---
**Author:** ![stevengj](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/stevengj/32/71_2.png) [@stevengj](https://discourse.julialang.org/u/stevengj)\ **Post date:** [July 6, 2023, 5:00pm UTC](https://discourse.julialang.org/t/calculating-first-integral/101267/2 "2023-07-06T17:00:27Z")
> [@Sergey\_Novak](#): > > Hello! I have an ODE system of 7 equations, and calculating the first integral analytically is a bit difficult for me. Are there packages for calculating the first integral of the ODE system? In general, there won’t be a closed form analytical integral of an ODE system, and you’ll have to solve the ODE numerically. For numerical ODE solvers in Julia, see [DifferentialEquations.jl](https://github.com/SciML/DifferentialEquations.jl) ---
**Author:** ![Sergey\_Novak](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/sergey_novak/32/37716_2.png) [@Sergey\_Novak](https://discourse.julialang.org/u/Sergey_Novak)\ **Post date:** [July 10, 2023, 10:11am UTC](https://discourse.julialang.org/t/calculating-first-integral/101267/3 "2023-07-10T10:11:31Z")
Thank you