<stránka

	xmlns="https://trac.frantovo.cz/xml-web-generator/wiki/xmlns/strana"

	xmlns:m="https://trac.frantovo.cz/xml-web-generator/wiki/xmlns/makro">

	<nadpis>Using boolean logic with AWK</nadpis>

	<perex>boolean data type and logical AND, OR, XOR operators</perex>

	<m:pořadí-příkladu>02500</m:pořadí-příkladu>

	<text xmlns="http://www.w3.org/1999/xhtml">

		<p>Expect that we have a relation with four combinations of logical values:</p>

		<pre><![CDATA[logic:

╭─────────────┬─────────────╮

│ a (boolean) │ b (boolean) │

├─────────────┼─────────────┤

│        true │        true │

│        true │       false │

│       false │        true │

│       false │       false │

╰─────────────┴─────────────╯

Record count: 4]]></pre>

		<p>

			we can use logical operators and functions:

		</p>

		<m:pre jazyk="bash"><![CDATA[relpipe-in-cli \

	generate logic 2 \

		a boolean \

		b boolean \

		true  true \

		true  false \

		false true \

		false false \

	| relpipe-tr-awk \

		--relation '.*' \

			--output-attribute AND boolean \

			--output-attribute OR  boolean \

			--output-attribute XOR boolean \

			--input-attributes-prepend \

			--for-each '{ AND = a && b; OR = a || b; XOR = xor(a,b); record(); }' \

	| relpipe-out-tabular]]></m:pre>

		<p>and append their results to the relation as additional attributes:</p>

		<pre><![CDATA[logic:

 ╭─────────────┬─────────────┬───────────────┬──────────────┬───────────────╮

 │ a (boolean) │ b (boolean) │ AND (boolean) │ OR (boolean) │ XOR (boolean) │

 ├─────────────┼─────────────┼───────────────┼──────────────┼───────────────┤

 │        true │        true │          true │         true │         false │

 │        true │       false │         false │         true │          true │

 │       false │        true │         false │         true │          true │

 │       false │       false │         false │        false │         false │

 ╰─────────────┴─────────────┴───────────────┴──────────────┴───────────────╯

Record count: 4]]></pre>

	</text>

</stránka>