Difference between revisions of "And"
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{{And}} | {{And}} | ||
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| + | The binary operator <syntaxhighlight lang="pascal" enclose="none">and</syntaxhighlight> performs a logical conjunction. | ||
| + | [[FPC]] also does a bitwise <syntaxhighlight lang="pascal" enclose="none">and</syntaxhighlight> when supplied with ordinal types. | ||
== Boolean operation == | == Boolean operation == | ||
| + | The operator <syntaxhighlight lang="pascal" enclose="none">and</syntaxhighlight> accepts to two Boolean type values. | ||
| + | It is the logical conjunction written in classic logic as <math>A \land B</math>. | ||
| + | Electrical engineers may write <math>A \times B</math> or <math>A \cdot B</math>, or eliminating the multiplication sign altogether writing <math>AB</math>. | ||
| + | However, the [[*|asterisk]] has a different meaning in programming. | ||
| + | The Boolean <syntaxhighlight lang="pascal" enclose="none">and</syntaxhighlight> evaluates to [[false and true|<syntaxhighlight lang="pascal" enclose="none">true</syntaxhighlight>]] if and only if both operands are <syntaxhighlight lang="pascal" enclose="none">true</syntaxhighlight>. | ||
| − | + | {| class="wikitable" style="text-align:center; margin:auto;" | |
| − | + | ! <syntaxhighlight lang="pascal" enclose="none">A</syntaxhighlight> | |
| − | === | + | ! <syntaxhighlight lang="pascal" enclose="none">B</syntaxhighlight> |
| − | + | ! <syntaxhighlight lang="pascal" enclose="none">A or B</syntaxhighlight> | |
| − | |||
|- | |- | ||
| − | + | | <syntaxhighlight lang="pascal" enclose="none">false</syntaxhighlight> | |
| + | | <syntaxhighlight lang="pascal" enclose="none">false</syntaxhighlight> | ||
| + | | style="background: #eeeeee" | <syntaxhighlight lang="pascal" enclose="none">false</syntaxhighlight> | ||
|- | |- | ||
| − | | | + | | <syntaxhighlight lang="pascal" enclose="none">false</syntaxhighlight> |
| − | |style="background: #eeeeee" | | + | | <syntaxhighlight lang="pascal" enclose="none">true</syntaxhighlight> |
| + | | style="background: #eeeeee" | <syntaxhighlight lang="pascal" enclose="none">false</syntaxhighlight> | ||
|- | |- | ||
| − | | | + | | <syntaxhighlight lang="pascal" enclose="none">true</syntaxhighlight> |
| − | |style="background: #eeeeee" | | + | | <syntaxhighlight lang="pascal" enclose="none">false</syntaxhighlight> |
| + | | style="background: #eeeeee" | <syntaxhighlight lang="pascal" enclose="none">false</syntaxhighlight> | ||
|- | |- | ||
| − | | | + | | <syntaxhighlight lang="pascal" enclose="none">true</syntaxhighlight> |
| − | | | + | | <syntaxhighlight lang="pascal" enclose="none">true</syntaxhighlight> |
| − | + | | style="background: #eeeeee" | <syntaxhighlight lang="pascal" enclose="none">true</syntaxhighlight> | |
| − | + | |+ truth table for logical conjunction | |
| − | |style="background: #eeeeee" | | ||
|} | |} | ||
== Bitwise operation == | == Bitwise operation == | ||
| + | FPC also defines a bitwise <syntaxhighlight lang="pascal" enclose="none">and</syntaxhighlight>. | ||
| + | Taking two ordinal operands logical <syntaxhighlight lang="pascal" enclose="none">and</syntaxhighlight> is calculated bit by bit: | ||
| + | 1010'1100 | ||
| + | and 0011'0100 | ||
| + | ―――――――――――― | ||
| + | 0010'0100 | ||
| − | + | == comparative remarks == | |
| − | + | Depending on the compiler's specific implementation of the data type [[Set|<syntaxhighlight lang="pascal" enclose="none">set</syntaxhighlight>]], the [[symmetric difference|symmetric difference of sets <syntaxhighlight lang="pascal" enclose="none">><</syntaxhighlight>]] virtually does the same as the bitwise <syntaxhighlight lang="pascal" enclose="none">and</syntaxhighlight>. | |
| − | == | ||
| − | |||
| − | |||
| − | |||
| − | |||
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| − | |||
| − | |||
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| − | [[ | + | == see also == |
| + | * [[Or|<syntaxhighlight lang="pascal" enclose="none">or</syntaxhighlight>]] | ||
Revision as of 13:13, 6 November 2018
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The binary operator and performs a logical conjunction.
FPC also does a bitwise and when supplied with ordinal types.
Boolean operation
The operator and accepts to two Boolean type values.
It is the logical conjunction written in classic logic as [math]\displaystyle{ A \land B }[/math].
Electrical engineers may write [math]\displaystyle{ A \times B }[/math] or [math]\displaystyle{ A \cdot B }[/math], or eliminating the multiplication sign altogether writing [math]\displaystyle{ AB }[/math].
However, the asterisk has a different meaning in programming.
The Boolean and evaluates to true if and only if both operands are true.
A
|
B
|
A or B
|
|---|---|---|
false
|
false
|
false
|
false
|
true
|
false
|
true
|
false
|
false
|
true
|
true
|
true
|
Bitwise operation
FPC also defines a bitwise and.
Taking two ordinal operands logical and is calculated bit by bit:
1010'1100
and 0011'0100
――――――――――――
0010'0100
comparative remarks
Depending on the compiler's specific implementation of the data type set, the symmetric difference of sets >< virtually does the same as the bitwise and.
