1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
|
{-# OPTIONS_GHC -Wall #-}
import Numeric.Sundials.ARKode.ODE
import Numeric.LinearAlgebra
import Plots as P
import qualified Diagrams.Prelude as D
import Diagrams.Backend.Rasterific
import Control.Lens
import Data.List (intercalate)
import Text.PrettyPrint.HughesPJClass
lorenz :: Double -> [Double] -> [Double]
lorenz _t u = [ sigma * (y - x)
, x * (rho - z) - y
, x * y - beta * z
]
where
rho = 28.0
sigma = 10.0
beta = 8.0 / 3.0
x = u !! 0
y = u !! 1
z = u !! 2
_lorenzJac :: Double -> Vector Double -> Matrix Double
_lorenzJac _t u = (3><3) [ (-sigma), rho - z, y
, sigma , -1.0 , x
, 0.0 , (-x) , (-beta)
]
where
rho = 28.0
sigma = 10.0
beta = 8.0 / 3.0
x = u ! 0
y = u ! 1
z = u ! 2
brusselator :: Double -> [Double] -> [Double]
brusselator _t x = [ a - (w + 1) * u + v * u * u
, w * u - v * u * u
, (b - w) / eps - w * u
]
where
a = 1.0
b = 3.5
eps = 5.0e-6
u = x !! 0
v = x !! 1
w = x !! 2
_brussJac :: Double -> Vector Double -> Matrix Double
_brussJac _t x = (3><3) [ (-(w + 1.0)) + 2.0 * u * v, w - 2.0 * u * v, (-w)
, u * u , (-(u * u)) , 0.0
, (-u) , u , (-1.0) / eps - u
]
where
y = toList x
u = y !! 0
v = y !! 1
w = y !! 2
eps = 5.0e-6
stiffish :: Double -> [Double] -> [Double]
stiffish t v = [ lamda * u + 1.0 / (1.0 + t * t) - lamda * atan t ]
where
lamda = -100.0
u = v !! 0
stiffishV :: Double -> Vector Double -> Vector Double
stiffishV t v = fromList [ lamda * u + 1.0 / (1.0 + t * t) - lamda * atan t ]
where
lamda = -100.0
u = v ! 0
stiffJac :: Double -> Vector Double -> Matrix Double
stiffJac _t _v = (1><1) [ lamda ]
where
lamda = -100.0
lSaxis :: [[Double]] -> P.Axis B D.V2 Double
lSaxis xs = P.r2Axis &~ do
let ts = xs!!0
us = xs!!1
vs = xs!!2
ws = xs!!3
P.linePlot' $ zip ts us
P.linePlot' $ zip ts vs
P.linePlot' $ zip ts ws
kSaxis :: [(Double, Double)] -> P.Axis B D.V2 Double
kSaxis xs = P.r2Axis &~ do
P.linePlot' xs
butcherTableauTex :: ButcherTable -> String
butcherTableauTex (ButcherTable m c b b2) =
render $
vcat [ text ("\n\\begin{array}{c|" ++ (concat $ replicate n "c") ++ "}")
, us
, text "\\hline"
, text bs <+> text "\\\\"
, text b2s <+> text "\\\\"
, text "\\end{array}"
]
where
n = rows m
rs = toLists m
ss = map (\r -> intercalate " & " $ map show r) rs
ts = zipWith (\i r -> show i ++ " & " ++ r) (toList c) ss
us = vcat $ map (\r -> text r <+> text "\\\\") ts
bs = " & " ++ (intercalate " & " $ map show $ toList b)
b2s = " & " ++ (intercalate " & " $ map show $ toList b2)
main :: IO ()
main = do
let res = butcherTable (SDIRK_2_1_2 undefined)
putStrLn $ show res
putStrLn $ butcherTableauTex res
let resA = butcherTable (KVAERNO_4_2_3 undefined)
putStrLn $ show resA
putStrLn $ butcherTableauTex resA
let resB = butcherTable (SDIRK_5_3_4 undefined)
putStrLn $ show resB
putStrLn $ butcherTableauTex resB
let res1 = odeSolve brusselator [1.2, 3.1, 3.0] (fromList [0.0, 0.1 .. 10.0])
renderRasterific "diagrams/brusselator.png"
(D.dims2D 500.0 500.0)
(renderAxis $ lSaxis $ [0.0, 0.1 .. 10.0]:(toLists $ tr res1))
let res1a = odeSolve brusselator [1.2, 3.1, 3.0] (fromList [0.0, 0.1 .. 10.0])
renderRasterific "diagrams/brusselatorA.png"
(D.dims2D 500.0 500.0)
(renderAxis $ lSaxis $ [0.0, 0.1 .. 10.0]:(toLists $ tr res1a))
let res2 = odeSolve stiffish [0.0] (fromList [0.0, 0.1 .. 10.0])
putStrLn $ show res2
renderRasterific "diagrams/stiffish.png"
(D.dims2D 500.0 500.0)
(renderAxis $ kSaxis $ zip [0.0, 0.1 .. 10.0] (concat $ toLists res2))
let res2a = odeSolveV (SDIRK_5_3_4 stiffJac) 0.1 1e-3 1e-6 stiffishV (fromList [0.0]) (fromList [0.0, 0.1 .. 10.0])
putStrLn "Lower tolerances"
putStrLn $ show res2a
let res3 = odeSolve lorenz [-5.0, -5.0, 1.0] (fromList [0.0, 0.01 .. 10.0])
putStrLn $ show $ last ((toLists $ tr res3)!!0)
let res3A = odeSolve lorenz [-5.0, -5.0, 1.0] (fromList [0.0, 0.01 .. 10.0])
putStrLn $ show $ last ((toLists $ tr res3A)!!0)
renderRasterific "diagrams/lorenz.png"
(D.dims2D 500.0 500.0)
(renderAxis $ kSaxis $ zip ((toLists $ tr res3)!!0) ((toLists $ tr res3A)!!1))
let res3a = odeSolve lorenz [-5.0, -5.0, 1.0] (fromList [0.0, 0.01 .. 10.0])
renderRasterific "diagrams/lorenzA.png"
(D.dims2D 500.0 500.0)
(renderAxis $ kSaxis $ zip ((toLists $ tr res3)!!0) ((toLists $ tr res3a)!!1))
renderRasterific "diagrams/lorenz1.png"
(D.dims2D 500.0 500.0)
(renderAxis $ kSaxis $ zip ((toLists $ tr res3)!!0) ((toLists $ tr res3)!!2))
renderRasterific "diagrams/lorenz2.png"
(D.dims2D 500.0 500.0)
(renderAxis $ kSaxis $ zip ((toLists $ tr res3)!!1) ((toLists $ tr res3)!!2))
|