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International journal of scientific and technical research in engineering (IJSTRE)
www.ijstre.com Volume 1 Issue 1 ǁ April 2016.
Manuscript id. 371428197 www.ijstre.com Page 18
Derivation of Three - Step Sixth Stage Runge-Kutta Method For
The Solution Of First Order Differential Equations
Mshelia DWa, Yakubu DG
b , Badmus AM
c and Manjak NH
b
a) Department of Mathematics, Umar Ibn Ibrahim Elkanami. College of Education, Science and technology, Bama
Borno State
Email [email protected]
b) Department of Mathematical Sciences, Abubakar Tafawa Balewa University Bauchi. Nigeria Email
c) Department of Mathematics, Nigerian Defence Academy,Kaduna. Nigeria
Email [email protected]
Abstract In this research paper, we extended the idea of Hybrid Block method at 𝑘 = 3 through interpolation
and collocation approaches to an effectively Sixth Stage Implicit Runge-Kutta method for the solution of initial
value problem of first order differential equations. The new approach displays a uniform order 6 schemes and
zero stable. The new method demonstrates superiority over its equivalent linear multi-step method (LMM) with
some numerical experiments tested.
Keyword: (Linear Multi-step method, Sixth stage, Runge-Kutta, Uniform order and Zero stable)
I. Introduction The development of numerical methods for approximating solutions of initial value problems (IVPs) in
ordinary differential equations (ODEs) has attracted considerable attention in recent decades and many
individuals have shown interest in constructing efficient methods with good stability properties for the
numerical integration of ordinary differential equations. Although, a very wide variety of numerical methods
have been proposed, the number of methods with high order and good stability properties remains relatively small. Among the methods for the numerical solutions of ODEs, the Discrete Value Methods (DVMs), which
systematically generate the approximate solutions {yn} along the step-point, {xn}, xn = a + nh, are the most
popular. Here h denotes the positive step size and yn is assumed to approximate y(xn), many of the existing
methods such as Euler method, Runge-Kutta methods and linear multistep methods fall into this category of
DVMs.
Runge-Kutta methods are among the most popular (ODEs) solvers, it was first studied by Carle Runge and
Martins Kutta around 1900. Runge-Kutta (RK) methods are single-step methods, they do not require successive
high derivatives of a function and therefore are general purpose initial value problem solvers. The most popular Runge-Kutta method is the Classical Runge-Kutta method of fourth order. It’s symmetrical in form and has
simple coefficients. The method is well suited for Computers because it needs no special starting procedure,
makes light demand on storage and repeatedly uses the same straight forward computational procedure. Its
numerically stable, unfortunately the early Runge-Kutta methods are explicit. Explicit RK methods are generally
unstable for the solution of Stiff equations because their region of absolute stable is small, in particular it’s
bounded. The instability of explicit Runge-Kutta methods motivates the development of implicit methods. We
consider implicit linear multistep methods and reformulated them into implicit RK methods with order 𝒑 =𝒔(𝒔𝒕𝒂𝒈𝒆𝒔)
1.1 Statement of the Problem
We want to develop highly efficient-Implicit Runge-Kutta integration formula at 𝒌 = 𝟑 for solution of first
order initial value problem of ordinary differential equations of the form
𝑦 ′ 𝑥 = 𝑓 𝑥, 𝑦 , 𝑦 0 = 𝑦0 (1.0)
1.2 Aim and Objectives
The aim of this research work is to Reformulation Linear multistep methods to its equivalent Runge-Kutta type
methods at 𝒌 = 𝟑 for the integration of Stiff and non stiff ordinary differential equations for first ODEs.
Derivation of Three - Step Sixth Stage Runge-Kutta Method For The Solution Of First Order
Differential Equations
Manuscript id. 371428197 www.ijstre.com Page 19
Objectives:
i) To derive self starting high order discrete and hybrid Schemes at 𝒌 = 𝟑 in Block form with their
Continuous formulations. The single Continuous formulation is evaluated at some selected points to obtain some discrete schemes which form the Block methods for solving (1.0)
ii) To Reformulate the block discrete methods into its equivalent Runge-Kutta methods of s stages
iii) To compare and contrast the efficiency of the methods and also implementation costs.
iv) To analysis the Block stability of the methods.
Theorem 1.0 Let I denote the identity matrix of dimension (𝑚 + 𝑡) x (𝑚 + 𝑡) and consider the matrices C and
D. Then
𝑖. 𝐷𝐶 = 𝐼
𝑖𝑖 𝑦 𝑥 = 𝐶𝑖+1,𝑗+1𝑦𝑛+𝑗
𝑡−1
𝑗 =0
+ 𝐶𝑖+1,𝑗+1𝑓𝑛+𝑗
𝑚−1
𝑗 =0
𝑥𝑖
𝑡+𝑚−1
𝑖=0
i.e. 𝐶 = 𝐷−1
for proof (see Onumanyi et al,1994)
1.3 Definition of Basic terms
Definition 1:-Zero stable:
A linear multi-step method is said to be Zero-stable if the roots 𝑅𝑗 , 𝑗 = 1 1 𝑘 of the first characteristics
polynomials
𝜌 𝑅 = 𝑑𝑒𝑡 𝐴𝑖𝑅𝑘−𝑖
𝑘
𝑖=0
= 0, 𝐴0 = −1, 𝑠𝑎𝑡𝑖𝑠𝑓𝑖𝑒𝑠 𝑅𝑗 ≤ 1
If one of the roots is +𝟏, we call this the principal root of 𝝆 𝑹 . Fatunla (1991)
Definition 2: Order and Error constants
A linear multi-step method
𝒚 𝑥 = 𝛼𝑗
𝑘
𝑗 =0
𝑥 𝑦𝑛+𝑗 = ℎ 𝛽𝑗
𝑘
𝑗 =0
(x)𝑓𝑛+𝑗 (𝟏. 𝟏)
we associate the linear differential operator
𝐿 𝑦 𝑥 ; ℎ = 𝛼𝑗 ;𝑦 𝑥 + 𝑗h − ℎ𝛽𝑗 𝑦′(𝑥; 𝑗h)
𝑘
𝑗 =0
( 1.2)
where 𝑦(𝑥) is an arbitrary function, continuously differentiable on [a, b]. Expanding the test function 𝑦 𝑥 +
𝑗ℎ and it’s derivative 𝑦′(𝑥+𝑗ℎ) as Taylor series about 𝑥 and collecting terms in (1.1) gives
𝐿 𝑦 𝑥 ; ℎ = 𝐶0𝑦 𝑥 + 𝐶1ℎ𝑦 ′ 𝑥 + ⋯ + 𝐶𝑞ℎ𝑞𝑦𝑞(𝑥) (1.3)
where 𝐶𝑞 are constants.
A simple calculation yields the following formulae for the constants 𝐶𝑞 in term of the coefficients 𝛼𝑗 , 𝛽𝑗 .
𝐶0 = ∝0 + ∝1+∝2 + ∝3+ …𝑘 ∝𝑘
𝐶1 = ∝1+ 2 ∝2 + 3 ∝3+ … +𝑘 ∝𝑘− (𝛽0 + 𝛽1 + 𝛽2 + ⋯ + 𝛽𝑘 )
𝐶𝑞 = 1
𝑞 !( ∝1+ 2𝑞 ∝2 + 3𝑞 ∝3+ … +𝑘𝑞 ∝𝑘) −
1
𝑞−1 !(𝛽1 + 2𝑞−1𝛽2 + … + 𝑘𝑞−1𝛽𝑘 ),
𝑞 = 2,3, … (1.4)
Following Henrici, P (1962), we say that the method has order P if
Derivation of Three - Step Sixth Stage Runge-Kutta Method For The Solution Of First Order
Differential Equations
Manuscript id. 371428197 www.ijstre.com Page 20
𝐶0 = 𝐶1 = 𝐶2 = ⋯𝐶𝑝 = 0 , 𝐶𝑝+1 ≠ 0
Hence, we say that the method has order P if 𝑪𝟎 = 𝑪𝟏 = 𝑪𝟐 = 𝑪𝒑 = 𝟎, But 𝑪𝒑+𝟏 ≠ 𝟎 then 𝑪𝒑+𝟏 is then the
error constant and 𝑪𝒑+𝟏𝒉𝒑+𝟏𝒚𝒑+𝟏(𝒙𝒏) the principal local truncated error at the point 𝒙𝒏. (see Lambert 1973)
II. Derivation of Sixth stage Runge-Kutta Methods at .𝒌 = 𝟑
Now we assume a power series solution of the form
𝑦 𝑥 = 𝛼𝑗 𝑥𝑗
𝑚+𝑡−1
𝑗 =0
(2.1)
as a basis solution for (1.0). Also the second derivative of (2.1) gives
𝑦′ 𝑥 = 𝑗𝛼𝑗 𝑥𝑗−1
𝑚+𝑡−1
𝑗 =0
(2.2)
Interpolating (2.1) at 𝑥 = 𝑥𝑛+𝑗 , 𝑗 = 0,1
2 ,1,
3
2 and collocating (2.2) at 𝑥 = 𝑥𝑛+𝑗 , 𝑗 = ,1,2 ,3. Specifically for this
method 𝑡 = 4 and 𝑚 = 3, the degree of the polynomial is 𝑚 + 𝑡 − 1 and we have the following system of non
linear equations
𝑎0 + 𝑎1𝑥𝑛 + 𝑎2𝑥𝑛2 + 𝑎3𝑥𝑛
3 + 𝑎4𝑥𝑛4 + 𝑎5𝑥𝑛
5 + 𝑎6𝑥𝑛6 = 𝑦𝑛
𝑎0 + 𝑎1𝑥𝑛+12
+ 𝑎2𝑥𝑛+12
2 + 𝑎3𝑥𝑛+12
3 + 𝑎4𝑥𝑛+12
4 + 𝑎5𝑥𝑛+12
5 + 𝑎6𝑥𝑛+12
6 = 𝑦𝑛+
12
𝑎0 + 𝑎1𝑥𝑛+1 + 𝑎2𝑥𝑛+12 + 𝑎3𝑥𝑛+1
3 + 𝑎4𝑥𝑛+14 + 𝑎5𝑥𝑛+1
5 + 𝑎6𝑥𝑛+16 = 𝑦𝑛+1
𝑎0 + 𝑎1𝑥𝑛+32
+ 𝑎2𝑥𝑛+
32
2 + 𝑎3𝑥𝑛+
32
3 + 𝑎4𝑥𝑛+
32
4 + 𝑎5𝑥𝑛+
32
5 + 𝑎6𝑥𝑛+
32
6 = 𝑦𝑛+
32
𝑎1 + 2𝑎2𝑥𝑛+1 + 3𝑎3𝑥𝑛+12 + 4𝑎4𝑥𝑛+1
3 + 5𝑎5𝑥𝑛+14 + 6𝑎6𝑥𝑛+1
5 = 𝑓𝑛 +1
𝑎1 + 2𝑎2𝑥𝑛+2 + 3𝑎3𝑥𝑛+22 + 4𝑎4𝑥𝑛+2
3 + 5𝑎5𝑥𝑛+24 + 6𝑎6𝑥𝑛+2
5 = 𝑓𝑛 +2
𝑎1 + 2𝑎2𝑥𝑛+3 + 3𝑎3𝑥𝑛+32 + 4𝑎4𝑥𝑛+3
3 + 5𝑎5𝑥𝑛+34 + 6𝑎6𝑥𝑛+3
5 = 𝑓𝑛 +3
(2.3)
By arranging (2.3) in Matrix equation form we have
1 𝑥𝑛 𝑥𝑛2 𝑥𝑛
3 𝑥𝑛4 𝑥𝑛
5 𝑥𝑛6
1 𝑥𝑛+
12
𝑥𝑛+
12
2 𝑥𝑛+
12
3 𝑥𝑛+
12
4 𝑥𝑛+12
5 𝑥𝑛+
12
6
1 𝑥𝑛+1 𝑥𝑛+12 𝑥𝑛+1
3 𝑥𝑛+14 𝑥𝑛+1
5 𝑥𝑛+16
1 𝑥𝑛+
32
𝑥𝑛+
32
2 𝑥𝑛+
32
3 𝑥𝑛+
32
4 𝑥𝑛+32
5 𝑥𝑛+
32
6
0 1 2𝑥𝑛+1 3𝑥𝑛+12 4𝑥𝑛+1
3 5𝑥𝑛+14 6𝑥𝑛+1
5
0 1 2𝑥𝑛+2 3𝑥𝑛+22 4𝑥𝑛+2
3 5𝑥𝑛+24 6𝑥𝑛+2
5
0 1 2𝑥𝑛+3 3𝑥𝑛+32 4𝑥𝑛+3
3 5𝑥𝑛+34 6𝑥𝑛+3
5
𝑎0
𝑎1
𝑎2
𝑎3
𝑎4
𝑎5
𝑎6
=
𝑦𝑛
𝑦𝑛+
12
𝑦𝑛+1
𝑦𝑛+
32
𝑓𝑛 +1
𝑓𝑛 +2
𝑓𝑛 +3
(2.4)
The continuous formula for (2.4) will be of the form
𝑦 𝑥 = 𝛼0𝑦𝑛 + 𝛼12𝑦
𝑛+12
+ 𝛼1𝑦𝑛+1 + 𝛼32𝑦
𝑛+3 2
+ ℎ 𝛽1𝑓𝑛 +1 + 𝛽2𝑓𝑛+2 + 𝛽3𝑓𝑛 +3 (2.5)
Using Maple 11 Mathematical software to evaluate the values of 𝑎𝑗 , ( 𝑗 = 0,1
2 , 1,
3
2 ,1 2,3) in (2.4) and
substituted in (2.5) to obtain our Continuous formula for this method as
Derivation of Three - Step Sixth Stage Runge-Kutta Method For The Solution Of First Order
Differential Equations
Manuscript id. 371428197 www.ijstre.com Page 21
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35
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4
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3
4
2
32
25
6
4
5
3
4
2
32
15
6
4
5
3
4
2
32
6
6
5
5
4
4
3
3
2
2
16
6
5
5
4
4
3
3
2
2
6
6
5
5
4
4
3
3
2
2
6
6
5
5
4
4
3
3
2
2
2
3
2
1
nnnn
nnnn
nn
nnnnn
n
nnnnn
n
nnnnn
nn
nnnn
nn
n
nnn
nnnn
nn
nnnn
fh
xx
h
xx
h
xx
h
xx
h
xxxxf
h
xx
h
xx
h
xx
h
xx
h
xxxxf
h
xx
h
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xx
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xx
h
xxxx
yh
xx
h
xx
h
xx
h
xx
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xx
h
xxy
h
xx
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xx
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h
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h
xxy
h
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xx
h
xx
h
xx
h
xxy
h
xx
h
xx
h
xx
h
xx
h
xx
h
xxxy
(2.6)
Evaluating (2,6) at 𝑥 = 𝑥𝑛+𝑗 , 𝑗 = 2,3 and the first derivative of (2.6) is evaluated at 𝑥 = 𝑥𝑛+𝑗 , 𝑗 =1
2,
3
2 to obtain
the following discrete schemes as our Block method at 𝑘 = 3
𝑦𝑛+2 +72
65𝑦𝑛+1 +
256
455𝑦
𝑛+12−
61
1365𝑦𝑛 =
27
35ℎ𝑓𝑛+1 +
102
455ℎ𝑓𝑛 +2 −
1
455ℎ𝑓𝑛+3
𝑦𝑛+3 +320
39𝑦
𝑛+32−
45
13𝑦𝑛+1 −
576
91𝑦
𝑛+12
+160
273𝑦𝑛 =
45
7ℎ𝑓𝑛 +1 +
180
91ℎ𝑓𝑛+2 +
25
91ℎ𝑓𝑛+3
26432𝑦𝑛+
32
+ 25704𝑦𝑛+1 − 74304𝑦𝑛+
12
+ 22168𝑦𝑛 = −4095ℎ𝑓𝑛 + 31239ℎ𝑓𝑛 +1
+1107ℎ𝑓𝑛+2 − 51ℎ𝑓𝑛+3
2032𝑦𝑛+
32
+ 5724𝑦𝑛+1 − 7344𝑦𝑛+
12− 412𝑦𝑛 =
1
1872ℎ𝑓
𝑛+12
+ 3159ℎ𝑓𝑛+1 + 72ℎ𝑓𝑛 +2
−3ℎ𝑓𝑛 +3
263312𝑦𝑛+
32− 212436𝑦𝑛+1 − 54864𝑦
𝑛+12
+ 3988𝑦𝑛 = 94419ℎ𝑓𝑛+1 − 4968ℎ𝑓𝑛+2
+65520ℎ𝑓𝑛+
32
+ 129ℎ𝑓𝑛+3
(2.7)
The method (2.7) is of Order 6,6,6,6,6]𝑇 with Error constants of 11
127400, −
19
10192, −
2487
560, −
249
1120, − 7041
1120 𝑇
By arranging (2.7) in Matrix equation form, we have
Derivation of Three - Step Sixth Stage Runge-Kutta Method For The Solution Of First Order
Differential Equations
Manuscript id. 371428197 www.ijstre.com Page 22
256
455
72
65
−512
195 1 0
−576
91
−45
13
320
39 0 1
74304 −25704 −26432 0 07344 −5724 −2032 0 0−54864 −212436 263312 0 0
𝑦
𝑛+12
𝑦𝑛+1
𝑦𝑛+
32
𝑦𝑛+2
𝑦𝑛+3
=
0 0 0 0
61
1365
0 0 0 0 −160
2730 0 0 0 −22168
0 0 0 0 4120 0 0 0 −3988
𝑦
𝑛−52
𝑦𝑛−2
𝑦𝑛−
32
𝑦𝑛−1
𝑦𝑛
+
0
−27
35 0
102
455
−1
455
0 45
7 0
180
91
25
910 −31239 0 −1107 51
−1872 −3159 0 −72 3 0 94419 65520 −4968 129
𝑓
𝑛+12
𝑓𝑛 +1
𝑓𝑛+
32
𝑓𝑛 +2
𝑓𝑛 +3
+
0 0 0 0 00 0 0 0 00 0 0 0 40950 0 0 0 00 0 0 0 0
𝑓
𝑛−52
𝑓𝑛−2
𝑓𝑛−
32
𝑓𝑛−1
𝑓𝑛
(2.8)
Let 𝐴(0) =
256
455
72
65
−512
195 1 0
−576
91
−45
13
320
39 0 1
74304 −25704 −26432 0 07344 −5724 −2032 0 0−54864 −212436 263312 0 0
By multiplying (2.8) by the inverse of 𝐴(0) and rearrange it in Butcher Table as
𝐶 𝐴
1
6
959
17280
35
216
−487
5760
49
1080
−211
17280
1
1920
1
3
169
3240
32
135
11
360
8
405
−7
1080
1
3240
1
2
103
1920
9
40
81
640
13
120
−9
640
1
1920
2
3
7
135
32
135
4
45
32
135
7
135
0
1 11
120
0 27
40
−8
15
27
40
11
1200
1 11
120
0 27
40
−8
15
27
40
11
1200
(2.9)
The Table (2.9) satisfies Runge-Kutta conditions for solution of first order ODEs since
𝑖 𝑎𝑖𝑗 = 𝑐𝑖
𝑠
𝑗 =1
𝑖𝑖 𝑏𝑗 = 1
𝑠
𝑗 =1
see Butcher 1996
The method (2.7) is formally given as Runge-Kutta type method as
)120
11
40
27
15
8
40
270
120
11( 6543211 kkkkkkhyy nn
where
nn yxfk ,1
Derivation of Three - Step Sixth Stage Runge-Kutta Method For The Solution Of First Order
Differential Equations
Manuscript id. 371428197 www.ijstre.com Page 23
)
1920
1
17280
211
1080
49
5760
487
216
35
17280
959(,
6
15543212 kkkkkkhyhxfk nn
)
3240
1
1080
7
405
8
360
11
135
32
3240
169(,
3
16543213 kkkkkkhyhxfk nn
)
1920
1
640
9
120
13
640
81
40
9
1920
103(,
3
16543214 kkkkkkhyhxfk nn
)*0
135
7
135
32
45
4
135
32
135
7(,
3
26543215 kkkkkkhyhxfk nn
)
120
11
40
27
15
8
40
27*0
120
11(, 6543216 kkkkkkhyhxfk nn
(2.10)
III. Consistency and Stability of the block scheme The sixth stage RK method
256
455
72
65
−512
195 1 0
−576
91
−45
13
320
39 0 1
74304 −25704 −26432 0 07344 −5724 −2032 0 0−54864 −212436 263312 0 0
𝑦
𝑛+12
𝑦𝑛+1
𝑦𝑛+
32
𝑦𝑛+2
𝑦𝑛+3
=
0 0 0 0
61
1365
0 0 0 0 −160
2730 0 0 0 −22168
0 0 0 0 4120 0 0 0 −3988
𝑦
𝑛−52
𝑦𝑛−2
𝑦𝑛−
32
𝑦𝑛−1
𝑦𝑛
+
0
−27
35 0
102
455
−1
455
0 45
7 0
180
91
25
910 −31239 0 −1107 51
−1872 −3159 0 −72 3 0 94419 65520 −4968 129
𝑓
𝑛+12
𝑓𝑛 +1
𝑓𝑛+
32
𝑓𝑛 +2
𝑓𝑛 +3
+
0 0 0 0 00 0 0 0 00 0 0 0 40950 0 0 0 00 0 0 0 0
𝑓
𝑛−52
𝑓𝑛−2
𝑓𝑛−
32
𝑓𝑛−1
𝑓𝑛
Let 𝐴(0) =
256
455
72
65
−512
195 1 0
−576
91
−45
13
320
39 0 1
74304 −25704 −26432 0 07344 −5724 −2032 0 0−54864 −212436 263312 0 0
When the first characteristic equation is multiplied by the inverse of 𝐴(0), and applied the condition of zero
stability we obtained the following
𝜌 𝑧 = 𝜆
1 0 0 0 00 1 0 0 00 0 1 0 00 0 0 1 00 0 0 0 1
−
0 0 0 0 −10 0 0 0 −10 0 0 0 −10 0 0 0 −10 0 0 0 −1
= 0
Derivation of Three - Step Sixth Stage Runge-Kutta Method For The Solution Of First Order
Differential Equations
Manuscript id. 371428197 www.ijstre.com Page 24
𝜆4 𝜆 − 1 = 0
𝜆1 = 0, 𝜆2 = 0, 𝜆3 = 0, 𝜆4 = 0, 𝜆5 = 1
From definition 1, the newly hybrid block method (2.7) is zero stable and also consistent since the order of all
the integrators in (2.7) are [6,6,6,6,6]𝑇 > 1
IV. Numerical Experiments
The following examples are used to confirm the efficiency of our method
Example 4.1
𝑦 ′ − 2𝑦 = 𝑒−𝑥 , 𝑦 0 =3
4 ℎ = 0.1 0 ≤ 𝑥 ≤ 1.0
Exact Solution: 𝑦 𝑥 = −1
3𝑒−3𝑥 +
13
12 𝑒2𝑥
Example 4.2
𝑦 ′ = 20𝑥2 − 20𝑦 + 2𝑥, 𝑦 0 =1
3 ℎ = 0.05 0 ≤ 𝑥 ≤ 1.0
Exact Solution: 𝑦 𝑥 = 𝑥2 +1
3𝑒−20𝑥
Example 4.3
𝑦 ′ = −𝑦, 𝑦 0 = 1 ℎ = 0.05 0 ≤ 𝑥 ≤ 1.0
Exact Solution: 𝑦 𝑥 = 𝑒−𝑥
Table 1: Approximate solution of Example 4.1 at k=3
Mesh value Exact solution Present Method at
k=3
Error of Present
Method at k=3
0.1 1.021573848000000 1.021573848000000 ---------------
0.2 1.343233171000000 1.343233171000000 -----------------
0.3 1.72702262600000 1.72702262600000 ------------------
0.4 2.18756265600000 2.18756265600000 ------------------
0.5 2.742628426000000 2.742628426000000 ----------------
0.6 3.413856121000000 3.413856119000000 2.0 E (-09)
0.7 4.227604866000000 4.227604860000000 3.0 E (-09)
0.8 5.216008802000000 5.216008801000000 1.0 E (-09)
0.9 6.418261528000000 6.418261529000000 1.0 E (-09)
1.0 7.882184294000000 7.882184288000000 6.0 E (-09)
Table 2: Approximate solution of Example 4.2 at k=3
Mesh value Yakubu et al (2004) Kwami (2011) Present Method k=3
0.05 4.6657 (E-04) 1.70624598 (E-07)
0.10 1.0629 (E-02) 4.2107 (E-05) 1.25538478 (E-07)
0.15 5.6175 (E-04) 6.927449 (E-08)
0.20 5.3890 (E-03) 6.4073 (E-04) 3.3979523 (E-08)
0.25 1.7049 (E-05) 1.562545 (E-08)
0.30 1.2320 (E-02) 5.3864 (E-04) 6.897933 (E-09)
0.35 1.9855 (E-04) 2.96054 (E-09)
0.40 1.3008 (E-03) 7.2861 (E-05) 1.24471 (E-09)
0.45 2.7302 (E-05) 5.1514 (E-10)
0.50 4.1148 (E-04) 1.0418 (E-05) 2.10566 (E-10)
0.55 3.6440 (E-06) 8.5209 (E-11)
0.60 3.9430 (E-4) 1.7999 (E-06) 3.4196 (E-11)
0.65 6.6250 (E-07) 1.363 (E-11)
0.70 4.0724 (-05) 2.4356 (E-07) 5.400 (E-12)
0.75 9.0031 (E-08) 2.131 (E-12)
Derivation of Three - Step Sixth Stage Runge-Kutta Method For The Solution Of First Order
Differential Equations
Manuscript id. 371428197 www.ijstre.com Page 25
0.80 1.3629 (E-05) 3.3443 (E-8) 8.360 (E-13)
0.85 1.2140 (E-8) 3.260 (E-13)
0.90 1.3672 (E-05) 4.8625 (E-09) 1.280 (E-13)
0.95 3.5210 (E-07) 4.70 (E-14)
1.00 1.4145 (E-06) 1.2680 (E-07) 1.0 (E-14)
Figure 1: Error graph of Example 4.2
Table 3: Approximate solution of Example 4.3 at k=3
Mesh values Yakubu et al
(2004) k = 3
Kwami (2011) k= 3 Present method k = 3
0.05 2.0291 x 10-11 1.0 x 10-15
0.10 2.1541 x 10-7 1.0482 x 10-11 2.0 x 10-15
0.15 3.0476 x 10-11 3.0 x 10-15
0.20 6.9544 x 10-8 4.9204 x 10-11 4.0 x 10-15
0.25 3.7974 x 10-11 5.0 x 10-15
0.30 2.8062 x 10-7 5.6549 x 10-11 6.0 x 10-15
0.35 6.8823 x 10-11 6.0 x 10-15
0.40 4.1350 x 10-7 5.8933 x 10-11 7.0 x 10-15
0.45 7,1250 x 10-11 7.0 x 10-15
0.50 2.8127 x 10-7 8.2750 x 10-11 7.0 x 10-15
0.55 7.2173 x 10-11 8.0 x 10-15
0.60 4.1578 x 10-7 8.3785x 10-11 7.0 x 10-15
0.65 9.0835 x 10-11 8.0 x 10-15
0.70 4.9444 x 10-7
8.1565 x 10-11
9.0 x 10-15
0.75 8.8840 x 10-11
9.0 x 10-15
0.80 3.7858 x 10-7 9.5601 x 10-11 9.0 x 10-15
0.85 8.6093 x 10-11 9.0 x 10-15
0.90 4.6203 x 10-7 9.3104 x 10-11 9.0 x 10-15
0.95 9.6813 x 10-11
9.0 x 10-15
1.0 5.0564 x 10-7 8.8506 x 10-11 9.0 x 10-15
0
0.002
0.004
0.006
0.008
0.01
0.012
1 2 3 4 5 6 7 8 9 10
Yakubu e tal 2004
Kwami 2011
Present Method
Derivation of Three - Step Sixth Stage Runge-Kutta Method For The Solution Of First Order
Differential Equations
Manuscript id. 371428197 www.ijstre.com Page 26
Figure 2: Error graph of Example 4.3 𝑎𝑡 𝑘 = 3
V. Discussion of Results In the three problems tested with our method, the numerical solution and absolute errors of example 4.1
is display in Table 1. The comparison of Absolute error of problem 2 with Yakubu et al (2004), Kwami (2011)
and our present method is displayed in Table 2 and figure 1, while the errors of problems 4.3 with different
methods were displayed in Table 3 and figure 2 respectively.
VI. Conclusion The implicit Block linear multi-step method 𝑎𝑡 𝑘 = 3 is reformulated to Sixth stage implicit Runge-
Kutta method. The advantage of this method is that in all the problems tested, the result obtained converges
better than the existing methods. (see Tables 1,2, 3 and error graphs 1 and 2)
References [1] Butcher J C (1996) A history of Runge-Kutta methods. Journal of Applied Numerical Mathematics.
Volume 20 pp247-260
[2] Fatunla S.O (1991)“Block Method for Second Order Differential Equations” International Journal of
Computer mathematics. 41: 55-63. [3] Henrici P (1962) Discrete variable methods in ordinary differential equations. John Willey and Sons
[4] Kwami AM (2011) A class of Continuous General Linear method for ordinary differential equations,
Ph.D Thesis (unpublished), Abubakar Tafawa Balawa University, Bauchi. Nigeria
[5] Lambert J.D (1973): Computational Methods in Ordinary Differential Equations .John Wiley and
Sons, New York. 278
[6] Mshelia DW, Yakubu DG , Badmus AM and Manjak NH (2015) A fifth stage Runge- Kutta method for
the Solution of ordinary differential equations submitted to Journal of Scientific Research and Report
[7] Yakubu, D.G, Onumanyi P and Chollom J P. (2004), A new family of general linear methods based on
the block Adams-Moulton multistep methods J. of pure and Applied Sciences, 7 (1): 98 – 106.
[8] Onumanyi P and Awoyemi D.O, Jator S.N. and Siriseria U.W.(1994) “ New Linear Multistep Methods
with continuous coefficients for first order ivps” Journal of Nigeria Mathematics society 13: 37- 51
0
0.000000
0.000000
0.000000
0.000000
0.000000
0.000000
1 2 3 4 5 6 7 8 9 10
Yakubu etal 2004
kwami 2011
Present method