ISSN: 1992-8645 www.jatit.org E-ISSN: 1817-3195
RESEARCH ON PROPERTIES OF E-PARTIAL DERIVATIVE
OF LOGIC FUNCTIONS
1WANG FANG
1Dept. of Computer and Information Technology, Zhejiang Changzheng Vocational and Technical College,
Hangzhou 310023; 2.Dept. of Information and Electronics Engineering, Zhejiang University, Hangzhou
310028
E-mail: [email protected]
ABSTRACT
E-derivative [1] has accessed a wide range of applications in these areas and caused academia concerned [1-4], such as detecting faults in combinational circuits, discussing on cryptographic properties of H-Boolean function and revealing the internal structure of H-Boolean function together with H-Boolean derivative, thus more effectively analyzing the property of Boolean functions. Referring to the discussion on Boolean derivative and Boolean partial derivative, the concept of
e
-partial derivative is presented. The definitions and properties ofe
-partial derivative and high ordere
-partial derivative are given. We also give their proofs for some properties. The work made in this paper is the complement and improvement of the research on thee
-derivative of logic functions.Key words: Logic Function;
e
-Derivative;e
-Partial Derivative; Special Operation Of Logic Function1. INTRODUCTIONS
Logic function
e
- derivative is a new special operation. Since the document [1] puts forwarde
-derivative, due to the unique characteristics ofe
-derivative, it has accessed a wide range of applications in these areas and caused academia concerned [1-4], such as detecting faults in combinational circuits, discussing on cryptographic properties of H-Boolean function and revealing the internal structure of Boolean function together with Boolean derivative, thus more effectively analyzing the property of Boolean functions. However, the document [1-4] simply discusses definition, properties and application of the first ordere
-derivative of logic function, the high ordere
-derivative ande
-partial derivative is a lack of research. Referring to the discussion of Boolean derivative and Boolean partial derivative of logic function, this article will study the logic functione
-partial derivative and its properties, and proof of some properties are given out, thus makes further complement and perfection ofe
-derivative study, in order to promote research on special operations.2. DEFINITION AND RELEVANT PROPERTY OF
e
- PARTIAL DERIVATIVEDocument [1] introduces definitions and properties of
e
-derivative, and this article just takes some relevant properties for example.Definition1 set
f x x
(
1~
n)
as variablen
fully defined logic functions, definition ofe
-derivative to the variablesx
i is:(
)
(
)
(
)
1
1 1
~
ni
i n i n
ef x x
ex
f x
x
x
f x
x
x
≡
⋅
(1.1)
Property 1.1
(
1 1) (
1 0)
i
n n
ef ex
f x x f x x
= ⋅
(1.2)
Property1
i i ef ef
ex ex =
(1.3 )
ISSN: 1992-8645 www.jatit.org E-ISSN: 1817-3195
Property 1.4
0
i i
ef df ex ⋅dx =
(1.5)
Formula
i
df dx
is the Boolean Difference, first order
e
-partial derivative.Property 1.5
(
) (
)
0i i
e f g e f g
ex ex
⋅ ⊕
⋅ = (1.6)
Formula “
⊕
”means XOR(exclusive OR)Property 1.6
(
)
i i i i
d f g
ef ef dg
ex dx ex dx
⊕
⋅ = ⋅ (1.7)
Property 1.7 IF
f
has no relationship withx
i, THENi
ef f ex =
(1.8)Property1.8 IF
variable
x
iis the linear variable off
,THEN0
i ef ex =
(1.9)
Property 1.9 IF 1
i
df dx =
,
THEN 0
i
ef ex =
(1.10)
Property 1.10 IF
1
i
ef
ex
=
,
THEN 0
i
df dx =
(1.11)
3. DEFINITION AND RELEVANT PROPERTY OF
e
-PARTIAL DERIVATIVEDefinition2 set
f x x
(
1~
n)
as variablen
fullydefined logic functions, first order
e
-partial derivativef
to the variablesx
i ise
-derivative.Definition 3 set
f x x
(
1~
n)
as variablen
fully defined logic functions, definition of second ordere
- partial derivativef
to the variablesi
x
、x
jis:
≡
j i j
i ex
ef ex
e ex ex
f e2
(2.1)
Definition 4 set
f x x
(
1~
n)
as variablen
fully defined logic functions, definition of K ordere
- partial derivativef
to the variables1
~
Ki i
x
x
is:
≡
K K i i i
i i
K
ex ef ex
e ex
e ex ex
f e
2
1
1 ~ (2.2)
Many properties of the
e
-partial derivatives can be directly deduced according to the definition ofe
-partial derivatives and related properties in§1,here only gives proof of some properties.
Property 2.1 2 2
i j j i
e f e f ex ex =ex ex
(2.3)
Deduction2.1 1 2 1
1
~ ~
~
K K
K
K K
i i i i i
K
i i
e f e f ex ex ex ex ex
e f ex ex
=
==
(2.4)
Property 2.2
2
i i i
e f ef ex ex =ex
(2.5)
Deduction 2.2 ~
K
i i i
K
e f ef ex ex =ex
(2.6)
Property 2.3
( ) ( ) ( ) ( )
200 01 10 11
i j
e f ex ex
f f f f
=
(2.7)
Proof
( ) ( )
(
0 1)
( ) ( ) ( ) ( )
00 01 10 112
f f f f x f x f ex
e ex ex
f e
i i i j i
= =
Deduction2.3
(
) (
)
(
) (
)
1~
0 00 0 01 1 10 1 11
K K i i e f ex ex
f f f f
=
(2.8)
Property 2.4
(
)
2 2
,
i j i j i j
e f e f ef ef ex ex =e x x ex ex
(2.9)
Formula
(
)
2
,
i j
e f e x x
ISSN: 1992-8645 www.jatit.org E-ISSN: 1817-3195
Proof
( )
( )
( )
( )
( )
( )
( )
( )
( ) ( ) ( )
22
,
i ji j
i j i j i j i j i j i j
i j i j i j i j i j
e f
ef ef
ex ex
e x x
f x x f x x f x x f x x f x x f x x
e f
f x x f x x f x x f x x
ex ex
=
=
=
Deduction 2.4
(
) (
)
(
) (
)
1
1 1 1
1
2 1 2
1
1 2
~
~ ~
~ ~
k
K K
K K K
K i i
K K
i i i i
K K
i i
i i i i
e f ex ex
e f e f e x x e x x
e f e f ef ef ex ex e x x e x x
−
−
−
− −
=
(2.10)
Property 2.5 2 2 0
i j i j
e f f ex ex x x
∂ =
∂ ∂ (2.11)
Formula
2
i j
f x x
∂
∂ ∂ is the Boolean second order
e
-Partial derivative
Proof
( )
( ) ( ) ( )
( )
( ) ( ) ( )
2 2
i j i j
i j i j i j i j
i j i j i j i j
e f f ex ex x x
f x x f x x f x x f x x
f x x f x x f x x f x x
∂ ∂ ∂ =
⊕ ⊕ ⊕
( )
( ) ( ) ( )
( )
( ) ( ) ( )
( )
( ) ( ) ( )
( )
( ) ( ) ( )
0 0 0i j i j i j i j
i j i j i j i j
i j i j i j i j
i j i j i j i j
f x x f x x f x x f x x
f x x f x x f x x f x x
f x x f x x f x x f x x
f x x f x x f x x f x x
=
⊕
⊕ ⊕
= ⊕ =
Deduction 2.5
1 1
0
~ ~
k K
K K
i i i i
e f f ex ex x x
∂ =
∂ ∂
(2.12)
Property 2.6
2 2
i j
i j
e f e f ex ex ex ex⋅ =
(2.13)
Deduction 2.6
1
1~ K ~ K
K K
i i
i i
e f e f ex ex ex ex =
(2.14)
Property 2.7 IF
f
=
a
( constant ) ,THEN 2
i j
e f a ex ex =
(2.15)
Deduction 2.7 IF
f
=
a
( constant ) , THEN1~ K
K
i i
e f a ex ex =
(2.16)
Property 2.8 IF
i j
ef ef f ex =ex =
,
THEN 2
i j
e f f ex ex =
(2.17)
Deduction2.8
1 2 K
i i i
ef ef ef
f ex =ex ==ex =
,THEN
1~ K K i i e f
f ex ex =
(2.18)
Property 2.9 2
(
)
2 2i j i j i j
e f g e f e g ex ex ex ex ex ex
⋅
= (2.19)
Deduction 2.9
(
)
1~ K 1~ K 1~ K
K K K
i i i i i i
e f g e f e g ex ex ex ex ex ex
⋅
=
(2.20)
Property 2.10
(
)
2
2 2 2
i j i j i j i j
f g
e f e f g
ex ex x x ex ex x x
∂ ⊕ = ∂
∂ ∂ ∂ ∂ ( 2.21)
Proof
(
)
( )
( ) ( ) ( )
( ) ( )
( ) ( )
2 2
[
i j i j
i j i j i j i j
i j i j i j i j
f g e f
ex ex x x
f x x f x x f x x f x x
f x x g x x f x x g x x
∂ ⊕
∂ ∂ =
⊕ ⊕ ⊕ ⊕
( ) ( ) ( ) ( )
( )
( ) ( ) ( )
( )
( )
( ) ( )
2 2]
[
]
i j i j i j i j
i j i j i j i j
i j i j
i j i j
i j i j
f x x g x x f x x g x x
f x x f x x f x x f x x
g x x g x x
e f g g x x g x x
ex ex x x
⊕ ⊕ ⊕
=
⊕ ⊕
∂
⊕ =
∂ ∂
Deduction 2.10
(
)
1 1
1 1
~ ~
~ ~
K K
K K K K
i i i i
K K
i i i i
f g e f
ex ex x x
e f g
ex ex x x
∂ ⊕ ∂ ∂
∂ =
∂ ∂
(2.22)
Property 2.11 2 2
(
)
0f g e f
ex ex x x
∂ + = ∂ ∂
ISSN: 1992-8645 www.jatit.org E-ISSN: 1817-3195
Proof
(
)
( )
( ) ( ) ( )
(
)
2 2
2
i j i j
i j i j i j i j
i j
f g e f
ex ex x x
f x x f x x f x x f x x
f g fg x x
∂ +
∂ ∂ =
∂ ⊕ ⊕
∂ ∂
( )
( ) ( ) ( )
( ) ( ) ( ) ( )
( ) ( ) ( ) ( )
[]
i j i j i j i j
i j i j i j i j
i
i j i j i j i j
f x x f x x f x x f x x
f x x g x x f x x g x x x
f x x g x x f x x g x x
=
∂ ⊕ ⊕
∂
⊕ ⊕ ⊕
( )
( ) ( ) ( )
( ) ( ) ( ) ( )
( ) ( ) ( ) ( )
[i j i j i j i j
i j i j i j i j
i j i j i j i j
f x x f x x f x x f x x
f x x g x x f x x g x x
f x x g x x f x x g x x
=
⊕ ⊕
⊕ ⊕ ⊕
( ) ( ) ( ) ( )
( ) ( ) ( ) ( )
]0 0 0 0 0 0 0
i j i j i j i j
i j i j i j i j
f x x g x x f x x g x x
f x x g x x f x x g x x
⊕ ⊕
⊕ ⊕ ⊕
= ⊕ ⊕ ⊕ ⊕ ⊕ =
Deduction2.1
(
)
1 1
0
~ K ~ K
K K
i i i i
f g e f
ex ex x x
∂ + = ∂ ∂
(2.24)
Property2.12 IF
f x x
(
1~
n)
has no relationshipwith
x
i、x
j,THEN
f ex ex
f e
j i
=
2
(2.25)
Deduction2.12 IF
f x x
(
1~
n)
has no relationship with1
~
Ki i
x
x
,THEN
1~ K K i i
e f f ex ex =
(2.26)
Property 2.13 IF one of
1
~
Ki i
x
x
is the linearvariable, THEN 2 0
i j
e f ex ex =
(2.27)
Proof Set
x
i as linear variable ,( )
xixj f( )
xixjf =
( )
( ) ( ) ( )
( ) ( ) ( ) ( )
2
0
i j i j i j i j
i j
i j i j i j i j
e f
f x x f x x f x x f x x ex ex
f x x f x x f x x f x x
=
= =
Deduction 2.13 IF one of
1
~
Ki i
x
x
is the linearvariable, THEN
1
0 ~
K K
i i
e f ex ex =
(2.28)
Property 2.14 IF 2
i j
e f f ex ex =
,
THEN K 0
i j
f x x
∂ = ∂ ∂
(2.29)
Proof
( )
i j( ) ( ) ( )
i j i j i j( )
i j ji
x x f x x f x x f x x f x x f ex ex
f
e2 = =
( )
xixj f( ) ( ) ( )
xixj f xixj f xixjf = = =
∴
So
( )
⊕( ) ( ) ( )
⊕ ⊕ =0⊕0=0= ∂ ∂
∂
j i j i j i j i j i K
x x f x x f x x f x x f x x
f
Deduction 2.14 IF
1~ K K i i e f
f ex ex =
,
THEN
1
0 ~ K
K
i i
f x x
∂ =
∂ ∂ (2.30)
Property 2.15 IF 2 1
i j
f x x
∂ =
∂ ∂ ,
THEN 2 0
i j
e f ex ex =
(2.31)
Proof
( )
i j( ) ( ) ( )
i j i j i j ji
x x f x x f x x f x x f x x
f
⊕ ⊕
⊕ =
∂ ∂
∂ = 2 1
( )
( ) ( ) ( )
( ) ( ) ( )
i j
i j i j i j
i j i j i j
f x x
f x x f x x f x x
f x x f x x f x x
∴
= ⊕ ⊕
= ⊕ ⊕
( )
( ) ( ) ( )
( ) ( ) ( )
(
)
( ) ( ) ( )
2
i j i j i j i j i j
i j i j i j
i j i j i j
e f
f x x f x x f x x f x x ex ex
f x x f x x f x x
f x x f x x f x x
=
= ⊕ ⊕
( ) ( ) ( )
( ) ( ) ( )
0i j i j i j
i j i j i j
f x x f x x f x x
f x x f x x f x x
=
ISSN: 1992-8645 www.jatit.org E-ISSN: 1817-3195
Deduction 2.15 IF
1
1 ~
K K i i
f x x
∂ = ∂ ∂
,
THEN
1
0 ~
K K i i
e f ex ex =
(2.32)
Property 2.16 IF
2
1
i j
e f ex ex =
,
THEN 2 0
i j
f x x
∂ =
∂ ∂ (2.33)
Proof
( )
( ) ( ) ( )
12
=
= i j i j i j i j
j i
x x f x x f x x f x x f ex ex
f e
( )
=( ) ( ) ( )
= = =1 ∴f xixj f xixj f xixj f xixj( )
( )
( ) ( )
2
1 1 1 1 0
i j i j
i j
i j i j
f
f x x f x x x x
f x x f x x
∂ = ⊕
∂ ∂
⊕ ⊕ = ⊕ ⊕ ⊕ =
Deduction2.16 IF
1
1 ~
K K i i
e f ex ex =
,
THEN
1 0
~ K
K i i
f x x
∂ = ∂ ∂
(2.34)
4. CONCLUSIONS
( 1 ) This article has studied the logic function
e
-partial derivative and its properties, and proof of some properties are given out, thus makes further complement and perfection ofe
-derivative study, and promoted research on special operations. Obviously,e
-derivative defined in document [1] is the special case ofe
-partial derivative when K=1. Properties ofe
-partial derivative in this paper are all suitable toe
-derivative. However, some of the properties ofe
-derivative are not applicable to the high ordere
-partial derivative. For example:i i i
i x
f dx df ex
f e ex ef
∂ ∂ = = +
j i j i j
i x x
f ex ex
f e ex ex
f e
∂ ∂
∂ ≠ + 2 2
2
(2) Property 2.4 explains relationship between high order
e
-partial derivative and high orderderivative, and Properties 2.5, 2.10, 2.11, 2.14, 2.15 and 2.16 explains relationship between higher order
e
-partial derivative and Boolean partial derivative. (3) Introduction ofe
-partial derivative improves research on the derivative, helps to reveal the property of Boolean functions. Application domains likee
-derivative, high ordere
-derivative ande
- partial derivative need to be further widened.REFERENCES
[1] LI W W, WANG z. The derivative of Boolean functions and its application in the fault detection and cryptographic system [J]. Kybernetes, 2008,37(2):49-65.
[2] LI W W, WANG z.,ZHANG z J. The application of derivative and
e
-derivative on H-Boolean functions [J]. CHINA SCI-TEC, 2008,(01):267-271.[3] DING Y J,WANG z, YE J H. Initial-value problem of the Boolean function’s primary function and its application in cryptographic system [J]. Kybernetes, 2010,39(6):900-906. [4] HE Liang, WANG zhuo, LI Wei-wei. Algorithm
of reducing the balanced H-Boolean function correlation-measure and research on correlative issue[J]. Journal of communications, 2010,31(2):93-99.
[5] OU Hai-wen,ZHANG Yu-juan. On algebraic immunity of a class of special Boolean functions[J].Application Research of Computers,2012.
[6]LIU Nan-nan,ZHAO Feng.The relationship between the algebraic immunity and nonlinearity of Boolean functions[J].Huaibei coal industry teachers College (Natural Science),2010.