Difference between revisions of "Xor"
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{{Xor}} | {{Xor}} | ||
| + | Back to [[Reserved words]]. | ||
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| + | The '''xor''' [[Operator|{{HL|operator}}]] compares two [[Boolean|{{HL|boolean}}]] values, and returns true if and only if one of them is true. | ||
= Boolean operation = | = Boolean operation = | ||
Exclusive or ('''xor''') results in a value of [[True|true]] if and only if exactly one of the operands has a value of true. | Exclusive or ('''xor''') results in a value of [[True|true]] if and only if exactly one of the operands has a value of true. | ||
| − | |||
== Truth table == | == Truth table == | ||
| − | {| | + | {| class="wikitable" |
|- | |- | ||
| − | ! | + | ! A !! B !! A xor B |
|- | |- | ||
| false || false | | false || false | ||
| Line 24: | Line 26: | ||
|style="background: #eeeeee" | false | |style="background: #eeeeee" | false | ||
|} | |} | ||
| − | |||
= Bitwise operation = | = Bitwise operation = | ||
Bitwise xor sets the bit to 1 where the corresponding bits in its operands are different, and to 0 if they are the same. | Bitwise xor sets the bit to 1 where the corresponding bits in its operands are different, and to 0 if they are the same. | ||
| + | |||
| + | Example: | ||
| + | |||
| + | 0101'1010 | ||
| + | xor 0011'0100 | ||
| + | ――――――――――――― | ||
| + | 0110'1110 | ||
== Toggle a bit == | == Toggle a bit == | ||
| − | < | + | <syntaxhighlight lang=pascal> |
function ToggleBit(const AValue,ABitNumber:integer):integer; | function ToggleBit(const AValue,ABitNumber:integer):integer; | ||
begin | begin | ||
result := AValue xor 1 shl ABitNumber; | result := AValue xor 1 shl ABitNumber; | ||
end; | end; | ||
| − | </ | + | </syntaxhighlight> |
| − | If you call ToggleBit(11,0) then get 10. If you call ToggleBit(10,2) then get 14. | + | If you call <syntaxhighlight lang="pascal" inline>ToggleBit(11,0)</syntaxhighlight> then get <syntaxhighlight lang="pascal" inline>10</syntaxhighlight>. If you call <syntaxhighlight lang="pascal" inline>ToggleBit(10,2)</syntaxhighlight> then get <syntaxhighlight lang="pascal" inline>14</syntaxhighlight>. |
| − | + | {{Logical operators}} | |
* [[Variable_parameter#XOR swap| XOR swap]] | * [[Variable_parameter#XOR swap| XOR swap]] | ||
| − | |||
* [[Const]] | * [[Const]] | ||
* [[Function]] | * [[Function]] | ||
* [[Integer]] | * [[Integer]] | ||
| + | |||
| + | [[Category:Code]] | ||
| + | [[Category:Operators]] | ||
Latest revision as of 05:21, 1 September 2021
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Back to Reserved words.
The xor operator compares two boolean values, and returns true if and only if one of them is true.
Boolean operation
Exclusive or (xor) results in a value of true if and only if exactly one of the operands has a value of true.
Truth table
| A | B | A xor B |
|---|---|---|
| false | false | false |
| false | true | true |
| true | false | true |
| true | true | false |
Bitwise operation
Bitwise xor sets the bit to 1 where the corresponding bits in its operands are different, and to 0 if they are the same.
Example:
0101'1010
xor 0011'0100
―――――――――――――
0110'1110
Toggle a bit
function ToggleBit(const AValue,ABitNumber:integer):integer;
begin
result := AValue xor 1 shl ABitNumber;
end;
If you call ToggleBit(11,0) then get 10. If you call ToggleBit(10,2) then get 14.
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| see also |
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