Skip to content

Commit 7b439ed

Browse files
Update ode_simple_nonlinear_prob.jl
1 parent 1c35661 commit 7b439ed

File tree

1 file changed

+13
-13
lines changed

1 file changed

+13
-13
lines changed

src/ode/ode_simple_nonlinear_prob.jl

Lines changed: 13 additions & 13 deletions
Original file line numberDiff line numberDiff line change
@@ -67,7 +67,7 @@ Van der Pol Equations
6767
\\frac{dy}{dt} = μ((1-x^2)y -x)
6868
```
6969
70-
with ``μ=1.0`` and ``u0=[0,\\sqrt{3}]``
70+
with ``μ=1.0`` and ``u_0=[0,\\sqrt{3}]``
7171
7272
Non-stiff parameters.
7373
"""
@@ -83,7 +83,7 @@ Van der Pol Equations
8383
\\frac{dy}{dt} = μ(1-x^2)y -x
8484
```
8585
86-
with ``μ=10^6`` and ``u0=[0,\\sqrt{3}]``
86+
with ``μ=10^6`` and ``u_0=[0,\\sqrt{3}]``
8787
8888
Stiff parameters.
8989
"""
@@ -139,22 +139,22 @@ end
139139
The ThreeBody problem as written by Hairer: (Non-stiff)
140140
141141
```math
142-
y₁′′ = y₁ + 2y₂′ - μ′\\frac{y₁+μ}{D₁} - μ\\frac{y₁-μ′}{D₂}
142+
\frac{dy₁}{dt} = y₁ + 2\frac{dy₂}{dt} - \bar{μ}\\frac{y₁+μ}{D₁} - μ\\frac{y₁-\bar{μ}}{D₂}
143143
```
144144
```math
145-
y₂′′ = y₂ - 2y₁′ - μ′\\frac{y₂}{D₁} - μ\\frac{y₂}{D₂}
145+
\frac{dy₂}{dt} = y₂ - 2\frac{dy₁}{dt} - \bar{μ}\\frac{y₂}{D₁} - μ\\frac{y₂}{D₂}
146146
```
147147
```math
148148
D₁ = ((y₁+μ)^2 + y₂^2)^{3/2}
149149
```
150150
```math
151-
D₂ = ((y₁-μ′)^2+y₂^2)^{3/2}
151+
D₂ = ((y₁-\bar{μ})^2+y₂^2)^{3/2}
152152
```
153153
```math
154154
μ = 0.012277471
155155
```
156156
```math
157-
μ′ =1-μ
157+
\bar{μ} =1-μ
158158
```
159159
160160
From Hairer Norsett Wanner Solving Ordinary Differential Equations I - Nonstiff Problems Page 129
@@ -224,10 +224,10 @@ end
224224
Pleiades Problem (Non-stiff)
225225
226226
```math
227-
xᵢ′′ = \\sum_{j≠i} mⱼ(xⱼ-xᵢ)/rᵢⱼ
227+
\frac{d^2xᵢ}{dt^2} = \\sum_{j≠i} mⱼ(xⱼ-xᵢ)/rᵢⱼ
228228
```
229229
```math
230-
yᵢ′′ = \\sum_{j≠i} mⱼ(yⱼ-yᵢ)/rᵢⱼ
230+
\frac{d^2yᵢ}{dt^2} = \\sum_{j≠i} mⱼ(yⱼ-yᵢ)/rᵢⱼ
231231
```
232232
233233
where
@@ -281,19 +281,19 @@ y₆(0) = -4
281281
y₇(0) = 4
282282
```
283283
284-
and with ``xᵢ′(0)=yᵢ′(0)=0`` except for
284+
and with ``\frac{dxᵢ(0)}{dt}=\frac{dyᵢ(0)}{dt}=0`` except for
285285
286286
```math
287-
x₆′(0) = 1.75
287+
\frac{dx₆(0)}{dt} = 1.75
288288
```
289289
```math
290-
x₇′(0) = -1.5
290+
\frac{dx₇(0)}{dt} = -1.5
291291
```
292292
```math
293-
y₄′(0) = -1.25
293+
\frac{dy₄(0)}{dt} = -1.25
294294
```
295295
```math
296-
y₅′(0) = 1
296+
\frac{dy₅(0)}{dt} = 1
297297
```
298298
299299
From Hairer Norsett Wanner Solving Ordinary Differential Equations I - Nonstiff Problems Page 244

0 commit comments

Comments
 (0)