Mercurial > repos > public > sbplib
annotate +time/Rk4SecondOrderNonlin.m @ 87:0a29a60e0b21
In Curve: Rearranged for speed. arc_length_fun is now a property of Curve. If it is not supplied, it is computed via the derivative and spline fitting. Switching to the arc length parameterization is much faster now. The new stuff can be tested with testArcLength.m (which should be deleted after that).
| author | Martin Almquist <martin.almquist@it.uu.se> |
|---|---|
| date | Sun, 29 Nov 2015 22:23:09 +0100 |
| 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 |