Remove examples from runtests.jl and add additional tests (#89)

* Added tests for problems in PDSProblemLibrary

* format

* Separated test for PDS problem library into two tests (adaptive schemes and non-adaptive schemes)

* Convergence tests for nonautonomous PDS and corresponding bug fixes

* format

* Skip test of MPRK43I(0.5,0.75) to solve prob_pds_stratreac

* Tests for compatibility of PositiveIntegrators and OrdinaryDiffEq

* Removed allocation tests for linear advection

* Skip solution of prob_pds_stratreac with MPRK43I(0.5,0.75) completely

* test plotting

* Update test/runtests.jl

Co-authored-by: Hendrik Ranocha <ranocha@users.noreply.github.com>

* Moved function definitions for testset 'Linear advection' out of the testset to avoid failing allocation tests

* Added Plots package for plotting tests

* Try to make allcoation tests in testset 'Linear advection' pass

* Test equality of MPRK22(alpha) and SSPMPRK22(0,alpha) also for nonconservative PDS

* Added comparision with correct derivative in 'Interpolation test (conservative)'.

* Additional test to check the differen possibilities to define small_constant

* Update test/runtests.jl

Co-authored-by: Hendrik Ranocha <ranocha@users.noreply.github.com>

* Update test/runtests.jl

Co-authored-by: Hendrik Ranocha <ranocha@users.noreply.github.com>

* Update test/runtests.jl

Co-authored-by: Hendrik Ranocha <ranocha@users.noreply.github.com>

* Clearer variable names in testset 'Linear advection'

* Meaningful function and variable names for the linear advection test

* Added tests for exact solutions of RK schemes and MPE

* Bug fix in 'Exact solutions (MPE)' test

* Compat entry for Plots

* update minimum version of Plots for Reexport compat

* Apply suggestions from code review

---------

Co-authored-by: Hendrik Ranocha <ranocha@users.noreply.github.com>

Author: SKopecz

src/mprk.jl

@@ -1012,13 +1012,13 @@ end
     # avoid division by zero due to zero Patankar weights
     σ = add_small_constant(σ, small_constant)
 
-    P3 = f.p(u, p, t + c2 * dt)
+    P3 = f.p(u, p, t + c3 * dt)
     Ptmp = b1 * P + b2 * P2 + b3 * P3
     integrator.stats.nf += 1
 
     # build linear system matrix
     if f isa PDSFunction
-        d3 = f.d(u, p, t + c2 * dt)  # evaluate nonconservative destruction terms
+        d3 = f.d(u, p, t + c3 * dt)  # evaluate nonconservative destruction terms
         dtmp = b1 * d + b2 * d2 + b3 * d3
         rhs = uprev + dt * diag(Ptmp)
         M = build_mprk_matrix(Ptmp, σ, dt, dtmp)

src/sspmprk.jl

@@ -157,13 +157,13 @@ end
     # avoid division by zero due to zero Patankar weights
     σ = add_small_constant(σ, small_constant)
 
-    P2 = f.p(u, p, t + a21 * dt)
+    P2 = f.p(u, p, t + b10 * dt)
     Ptmp = b20 * P + b21 * P2
     integrator.stats.nf += 1
 
     # build linear system matrix and rhs
     if f isa PDSFunction
-        d2 = f.d(u, p, t + a21 * dt)  # evaluate nonconservative destruction terms
+        d2 = f.d(u, p, t + b10 * dt)  # evaluate nonconservative destruction terms
         dtmp = b20 * d + b21 * d2
         rhs = a20 * uprev + a21 * u + dt * diag(Ptmp)
         M = build_mprk_matrix(Ptmp, σ, dt, dtmp)
@@ -300,8 +300,8 @@ end
     end
     @.. broadcast=false σ=σ + small_constant
 
-    f.p(P2, u, p, t + a21 * dt) # evaluate production terms
-    f.d(D2, u, p, t + a21 * dt) # evaluate nonconservative destruction terms
+    f.p(P2, u, p, t + b10 * dt) # evaluate production terms
+    f.d(D2, u, p, t + b10 * dt) # evaluate nonconservative destruction terms
     integrator.stats.nf += 1
 
     @.. broadcast=false P2=b20 * P + b21 * P2
@@ -372,7 +372,7 @@ end
     end
     @.. broadcast=false σ=σ + small_constant
 
-    f.p(P2, u, p, t + a21 * dt) # evaluate production terms
+    f.p(P2, u, p, t + b10 * dt) # evaluate production terms
     integrator.stats.nf += 1
 
     @.. broadcast=false P2=b20 * P + b21 * P2

test/Project.toml

@@ -3,6 +3,7 @@ Aqua = "4c88cf16-eb10-579e-8560-4a9242c79595"
 LinearAlgebra = "37e2e46d-f89d-539d-b4ee-838fcccc9c8e"
 LinearSolve = "7ed4a6bd-45f5-4d41-b270-4a48e9bafcae"
 OrdinaryDiffEq = "1dea7af3-3e70-54e6-95c3-0bf5283fa5ed"
+Plots = "91a5bcdd-55d7-5caf-9e0b-520d859cae80"
 SparseArrays = "2f01184e-e22b-5df5-ae63-d93ebab69eaf"
 StaticArrays = "90137ffa-7385-5640-81b9-e52037218182"
 Statistics = "10745b16-79ce-11e8-11f9-7d13ad32a3b2"
@@ -12,5 +13,6 @@ Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
 Aqua = "0.7, 0.8"
 LinearSolve = "2.21"
 OrdinaryDiffEq = "6.59"
+Plots = "1.11.1"
 StaticArrays = "1.5"
 Statistics = "1"