Lisp-bitwise-operators

LISP-ビット演算子

ビットごとの演算子はビットに対して機能し、ビットごとの操作を実行します。 ビットごとのAND、OR、およびXOR演算の真理値表は次のとおりです-

p	q	p and q	p or q	p xor q
0	0	0	0	0
0	1	0	1	1
1	1	1	1	0
1	0	0	1	1

Assume if A = 60; and B = 13; now in binary format they will be as follows:
A = 0011 1100
B = 0000 1101
-----------------
A and B = 0000 1100
A or B = 0011 1101
A xor B = 0011 0001
not A  = 1100 0011

次の表に、LISPでサポートされているビット単位の演算子を示します。 変数Aが60を保持し、変数Bが13を保持すると仮定します-

Operator	Description	Example
logand	This returns the bit-wise logical AND of its arguments. If no argument is given, then the result is -1, which is an identity for this operation.	(logand a b)) will give 12
logior	This returns the bit-wise logical INCLUSIVE OR of its arguments. If no argument is given, then the result is zero, which is an identity for this operation.	(logior a b) will give 61
logxor	This returns the bit-wise logical EXCLUSIVE OR of its arguments. If no argument is given, then the result is zero, which is an identity for this operation.	(logxor a b) will give 49
lognor	This returns the bit-wise NOT of its arguments. If no argument is given, then the result is -1, which is an identity for this operation.	(lognor a b) will give -62,
logeqv	This returns the bit-wise logical EQUIVALENCE (also known as exclusive nor) of its arguments. If no argument is given, then the result is -1, which is an identity for this operation.	(logeqv a b) will give -50

例

main.lispという名前の新しいソースコードファイルを作成し、次のコードを入力します。

(setq a 60)
(setq b 13)

(format t "~% BITWISE AND of a and b is ~a" (logand a b))
(format t "~% BITWISE INCLUSIVE OR of a and b is ~a" (logior a b))
(format t "~% BITWISE EXCLUSIVE OR of a and b is ~a" (logxor a b))
(format t "~% A NOT B is ~a" (lognor a b))
(format t "~% A EQUIVALANCE B is ~a" (logeqv a b))

(terpri)
(terpri)

(setq a 10)
(setq b 0)
(setq c 30)
(setq d 40)

(format t "~% Result of bitwise and operation on 10, 0, 30, 40 is ~a" (logand a b c d))
(format t "~% Result of bitwise or operation on 10, 0, 30, 40 is ~a" (logior a b c d))
(format t "~% Result of bitwise xor operation on 10, 0, 30, 40 is ~a" (logxor a b c d))
(format t "~% Result of bitwise eqivalance operation on 10, 0, 30, 40 is ~a" (logeqv a b c d))

実行ボタンをクリックするか、Ctrl + Eを入力すると、LISPはすぐに実行し、返される結果は-

BITWISE AND of a and b is 12
BITWISE INCLUSIVE OR of a and b is 61
BITWISE EXCLUSIVE OR of a and b is 49
A NOT B is -62
A EQUIVALANCE B is -50

Result of bitwise and operation on 10, 0, 30, 40 is 0
Result of bitwise or operation on 10, 0, 30, 40 is 62
Result of bitwise xor operation on 10, 0, 30, 40 is 60
Result of bitwise eqivalance operation on 10, 0, 30, 40 is -61