Embedded methods List of Runge–Kutta methods
1 embedded methods
1.1 heun–euler
1.2 fehlberg rk1(2)
1.3 bogacki–shampine
1.4 fehlberg
1.5 cash-karp
1.6 dormand–prince
embedded methods
the embedded methods designed produce estimate of local truncation error of single runge-kutta step, , result, allow control error adaptive stepsize. done having 2 methods in tableau, 1 order p , 1 order p-1.
the lower-order step given by
y
n
+
1
∗
=
y
n
+
h
∑
i
=
1
s
b
i
∗
k
i
,
{\displaystyle y_{n+1}^{*}=y_{n}+h\sum _{i=1}^{s}b_{i}^{*}k_{i},}
where
k
i
{\displaystyle k_{i}}
same higher order method. error is
e
n
+
1
=
y
n
+
1
−
y
n
+
1
∗
=
h
∑
i
=
1
s
(
b
i
−
b
i
∗
)
k
i
,
{\displaystyle e_{n+1}=y_{n+1}-y_{n+1}^{*}=h\sum _{i=1}^{s}(b_{i}-b_{i}^{*})k_{i},}
which
o
(
h
p
)
{\displaystyle o(h^{p})}
. butcher tableau kind of method extended give values of
b
i
∗
{\displaystyle b_{i}^{*}}
c
1
a
11
a
12
…
a
1
s
c
2
a
21
a
22
…
a
2
s
⋮
⋮
⋮
⋱
⋮
c
s
a
s
1
a
s
2
…
a
s
s
b
1
b
2
…
b
s
b
1
∗
b
2
∗
…
b
s
∗
{\displaystyle {\begin{array}{c|cccc}c_{1}&a_{11}&a_{12}&\dots &a_{1s}\\c_{2}&a_{21}&a_{22}&\dots &a_{2s}\\\vdots &\vdots &\vdots &\ddots &\vdots \\c_{s}&a_{s1}&a_{s2}&\dots &a_{ss}\\\hline &b_{1}&b_{2}&\dots &b_{s}\\&b_{1}^{*}&b_{2}^{*}&\dots &b_{s}^{*}\\\end{array}}}
heun–euler
the simplest adaptive runge–kutta method involves combining heun s method, order 2, euler method, order 1. extended butcher tableau is:
0
1
1
1
/
2
1
/
2
1
0
{\displaystyle {\begin{array}{c|cc}0&\\1&1\\\hline &1/2&1/2\\&1&0\end{array}}}
the error estimate used control stepsize.
fehlberg rk1(2)
the fehlberg method has 2 methods of orders 1 , 2. extended butcher tableau is:
the first row of b coefficients gives first-order accurate solution, , second row has order two.
bogacki–shampine
the bogacki–shampine method has 2 methods of orders 3 , 2. extended butcher tableau is:
the first row of b coefficients gives third-order accurate solution, , second row has order two.
fehlberg
the runge–kutta–fehlberg method has 2 methods of orders 5 , 4. extended butcher tableau is:
the first row of b coefficients gives fifth-order accurate solution, , second row has order four.
cash-karp
cash , karp have modified fehlberg s original idea. extended tableau cash–karp method is
the first row of b coefficients gives fifth-order accurate solution, , second row has order four.
dormand–prince
the extended tableau dormand–prince method is
the first row of b coefficients gives fifth-order accurate solution , second row gives fourth-order accurate solution.
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