# \#diferential-equation

**URL:** https://discourse.julialang.org/tag/diferential-equation/718.md

[Latest](https://discourse.julialang.org/latest.md) · [Categories](https://discourse.julialang.org/categories.md) · [Tags](https://discourse.julialang.org/tags.md)

---

## [Julia runs slower after many loop iterations (solve ODE problem)](https://discourse.julialang.org/t/julia-runs-slower-after-many-loop-iterations-solve-ode-problem/124238)

<div class="topic-metadata">

**Author:** [@chooron](https://discourse.julialang.org/u/chooron)\
**Replies:** 3\
**Last updated:** [December 29, 2024, 4:00am UTC](https://discourse.julialang.org/t/julia-runs-slower-after-many-loop-iterations-solve-ode-problem/124238 "2024-12-29T04:00:38Z")

</div>

Hello, I need to perform optimization of many groups of ODE problems. The optimization time required for the first few groups is about 20 minutes, but after completing multiple optimizations, the time required gradually …

---

## [What can I do to calculate the L2 norm between the exact solution and my numerical solution?](https://discourse.julialang.org/t/what-can-i-do-to-calculate-the-l2-norm-between-the-exact-solution-and-my-numerical-solution/114359)

<div class="topic-metadata">

**Author:** [@mcr.92](https://discourse.julialang.org/u/mcr.92)\
**Replies:** 3\
**Last updated:** [May 16, 2024, 2:23pm UTC](https://discourse.julialang.org/t/what-can-i-do-to-calculate-the-l2-norm-between-the-exact-solution-and-my-numerical-solution/114359 "2024-05-16T14:23:52Z")

</div>

I am solving a differential equation by the MOL method, it has an exact solution so I want to calculate the error in the L2 norm. I made this code F1(x) = A\*(cosh(B\*x)) F2(y) = A\*(cosh(B\*y)) FC = -(2\*(B^2)\*K - W)/(ρ\*C\_s…

---

## [Adding set of equations in ModelingToolkit](https://discourse.julialang.org/t/adding-set-of-equations-in-modelingtoolkit/100019)

<div class="topic-metadata">

**Author:** [@Ethan\_Tran](https://discourse.julialang.org/u/Ethan_Tran)\
**Replies:** 1\
**Last updated:** [June 7, 2023, 7:55pm UTC](https://discourse.julialang.org/t/adding-set-of-equations-in-modelingtoolkit/100019 "2023-06-07T19:55:05Z")

</div>

I have several sets of differential equations, and to reduce the time of implementation I try to implement each set of equations by for loop as below (just for example): @variable (x(t))\[1:n\] (y(t))\[1:n\] eq1 = \[0 ~ D(x\[…

---

## [Static Vector with two different units](https://discourse.julialang.org/t/static-vector-with-two-different-units/63070)

<div class="topic-metadata">

**Author:** [@Luapulu](https://discourse.julialang.org/u/Luapulu)\
**Replies:** 1\
**Last updated:** [June 17, 2021, 8:15am UTC](https://discourse.julialang.org/t/static-vector-with-two-different-units/63070 "2021-06-17T08:15:36Z")

</div>

I’m working with DifferentialEquations.jl and I have a state vector in 6-dimensional phase space. I would like to work with units and static vectors but my issue is that the momentum part of the phase space vector has a …