WIP: IMEX tableau prototype - fix perform_step and formatting

Author: Harsh Singh

lib/OrdinaryDiffEqSDIRK/src/generic_imex_perform_step.jl

@@ -79,7 +79,7 @@ function initialize!(integrator, cache::IMEXConstantCache)
     OrdinaryDiffEqCore.increment_nf!(integrator.stats, 1)
     integrator.fsallast = zero(integrator.fsalfirst)
     integrator.k[1] = integrator.fsalfirst
-    integrator.k[2] = integrator.fsallast
+    return integrator.k[2] = integrator.fsallast
 end
 
 function initialize!(integrator, cache::IMEXCache)
@@ -88,7 +88,7 @@ function initialize!(integrator, cache::IMEXCache)
     integrator.k[1] = integrator.fsalfirst
     integrator.k[2] = integrator.fsallast
     integrator.f(integrator.fsalfirst, integrator.uprev, integrator.p, integrator.t)
-    OrdinaryDiffEqCore.increment_nf!(integrator.stats, 1)
+    return OrdinaryDiffEqCore.increment_nf!(integrator.stats, 1)
 end
 
 @muladd function perform_step!(

lib/OrdinaryDiffEqSDIRK/src/imex_tableaus.jl

@@ -137,8 +137,10 @@ function KenCarp3IMEXTableau(T, T2)
     α_mat[4, 1] = α41
     α_mat[4, 2] = α42
 
-    return IMEXTableau(Ai, bi_vec, Ae, be_vec, c_vec,
-        btilde_vec, ebtilde_vec, α_mat, 3, s)
+    return IMEXTableau(
+        Ai, bi_vec, Ae, be_vec, c_vec,
+        btilde_vec, ebtilde_vec, α_mat, 3, s
+    )
 end
 
 function ARS343Tableau(T, T2)
@@ -189,6 +191,8 @@ function ARS343Tableau(T, T2)
 
     α_mat = zeros(T2, s, s)
 
-    return IMEXTableau(Ai, bi_vec, Ae, be_vec, c_vec,
-        btilde_vec, ebtilde_vec, α_mat, 3, s)
+    return IMEXTableau(
+        Ai, bi_vec, Ae, be_vec, c_vec,
+        btilde_vec, ebtilde_vec, α_mat, 3, s
+    )
 end