Mercurial > repos > public > sbplib
annotate +time/Rk4SecondOrderNonlin.m @ 1198:2924b3a9b921 feature/d2_compatible
Add OpSet for fully compatible D2Variable, created from regular D2Variable by replacing d1 by first row of D1. Formal reduction by one order of accuracy at the boundary point.
author | Martin Almquist <malmquist@stanford.edu> |
---|---|
date | Fri, 16 Aug 2019 14:30:28 -0700 |
parents | cd2e28c5ecd2 |
children | b5e5b195da1e c6fcee3fcf1b |
rev | line source |
---|---|
0 | 1 classdef Rk4SecondOrderNonlin < time.Timestepper |
2 properties | |
3 F | |
4 k | |
5 t | |
6 w | |
7 m | |
8 | |
9 D | |
10 E | |
11 S | |
12 | |
13 n | |
14 end | |
15 | |
16 | |
17 methods | |
18 function obj = Rk4SecondOrderNonlin(D, E, S, k, t0, v0, v0t) | |
1
5ae4f23d9130
Added CdiffNonlin timestepper. Probably fixed a bug with Cdiff. Added default arguments to Rk4SecondOrderNonlin.
Jonatan Werpers <jonatan@werpers.com>
parents:
0
diff
changeset
|
19 default_arg('S',0); |
5ae4f23d9130
Added CdiffNonlin timestepper. Probably fixed a bug with Cdiff. Added default arguments to Rk4SecondOrderNonlin.
Jonatan Werpers <jonatan@werpers.com>
parents:
0
diff
changeset
|
20 default_arg('E',0); |
0 | 21 |
30
cd2e28c5ecd2
Corrected parameter treatment in nonlin timesteppers.
Jonatan Werpers <jonatan@werpers.com>
parents:
28
diff
changeset
|
22 if isnumeric(S) |
cd2e28c5ecd2
Corrected parameter treatment in nonlin timesteppers.
Jonatan Werpers <jonatan@werpers.com>
parents:
28
diff
changeset
|
23 S = @(v,t)S; |
0 | 24 end |
25 | |
30
cd2e28c5ecd2
Corrected parameter treatment in nonlin timesteppers.
Jonatan Werpers <jonatan@werpers.com>
parents:
28
diff
changeset
|
26 if isnumeric(E) |
cd2e28c5ecd2
Corrected parameter treatment in nonlin timesteppers.
Jonatan Werpers <jonatan@werpers.com>
parents:
28
diff
changeset
|
27 E = @(v)E; |
0 | 28 end |
29 | |
30 obj.k = k; | |
31 obj.t = t0; | |
32 obj.w = [v0; v0t]; | |
33 | |
34 m = length(v0); | |
35 function wt = F(w,t) | |
36 v = w(1:m); | |
37 vt = w(m+1:end); | |
38 | |
39 % Def: w = [v; vt] | |
40 wt(1:m,1) = vt; | |
41 wt(m+1:2*m,1) = D(v)*v + E(v)*vt + S(v,t); | |
42 | |
43 end | |
44 | |
45 obj.F = @F; | |
46 obj.D = D; | |
47 obj.E = E; | |
48 obj.S = S; | |
49 obj.m = m; | |
13
b18d3d201a71
Fixed initialization of step counter in timesteppers.
Jonatan Werpers <jonatan@werpers.com>
parents:
1
diff
changeset
|
50 obj.n = 0; |
0 | 51 end |
52 | |
53 function [v,t] = getV(obj) | |
54 v = obj.w(1:end/2); | |
55 t = obj.t; | |
56 end | |
57 | |
58 function [vt,t] = getVt(obj) | |
59 vt = obj.w(end/2+1:end); | |
60 t = obj.t; | |
61 end | |
62 | |
63 function obj = step(obj) | |
64 obj.w = time.rk4.rungekutta_4(obj.w, obj.t, obj.k, obj.F); | |
65 obj.t = obj.t + obj.k; | |
66 obj.n = obj.n + 1; | |
67 end | |
68 end | |
69 | |
70 | |
71 methods (Static) | |
72 function k = getTimeStep(lambda) | |
73 k = rk4.get_rk4_time_step(lambda); | |
74 end | |
75 end | |
76 | |
77 end |