PERK p2

[warisa-r]

Hello,

this branch adds a new time integrator of second-order paired explicit Runge-Kutta method.
It contains the time integrator, a polynomial optimizer for the method, and a new elixir employing the second-order P-ERK time integration scheme with 6 stages.

[DanielDoehring]

For some reason the SummaryCallback causes the allocations causing the test to fail.

This is observed also for the other custom integrators, see

Trixi.jl/test/test_tree_2d_advection.jl

Lines 153 to 166 in 2dfde7f

	@trixi_testset "elixir_advection_timeintegration.jl" begin
	@test_trixi_include(joinpath(EXAMPLES_DIR, "elixir_advection_timeintegration.jl"),
	l2=[2.4976030518356626e-5],
	linf=[0.0005531580316338533],
	# Let this test terminate by time instead of maxiters to cover some lines
	# in time_integration/methods_2N.jl
	coverage_override=(maxiters = 10^5, tspan = (0.0, 0.1)))
	# Ensure that we do not have excessive memory allocations
	# (e.g., from type instabilities)
	let
	t = sol.t[end]
	u_ode = sol.u[end]
	du_ode = similar(u_ode)
	@test (@allocated Trixi.rhs!(du_ode, u_ode, semi, t)) < 15000

and the other tests.

[DanielDoehring]

Not sure if I can add a version for DelimitedFiles as I get for DelimitedFiles = "1.9.0"

  ERROR: LoadError: Unsatisfiable requirements detected for package DelimitedFiles [8bb1440f]:
 DelimitedFiles [8bb1440f] log:
 ├─possible versions are: 1.9.0-1.9.1 or uninstalled
 └─restricted to versions 1.8.5-1.8 by Trixi [a7f1ee26] — no versions lef

and for DelimitedFiles=1.8.5 (for which no release seems to exist)

 ERROR: LoadError: Unsatisfiable requirements detected for package DelimitedFiles [8bb1440f]:
DelimitedFiles [8bb1440f] log:
├─possible versions are: 1.8.5 or uninstalled (package in sysimage!)
└─restricted to versions 1.9.0-1 by Trixi [a7f1ee26] — no versions left

@JoshuaLampert

[JoshuaLampert]

Yes, for the Downgrade action that's to be expected as DelimitedFiles is a stdlib. It should be added to the list of skipped libraries. The compat could then be DelimitedFiles = "1.9.0". You could also try DelimitedFiles = "1".

[JoshuaLampert]

A bit of context for why we need the compat: https://discourse.julialang.org/t/psa-compat-requirements-in-the-general-registry-are-changing/104958 and #1711.

[DanielDoehring]

You could also try DelimitedFiles = "1".

That seems to work, thanks!

[warisa-r]

Close this one for now. Working on making Convex and ECOS extensions rather than direct dependencies.