--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/relpipe-data/examples-awk-boolean-logic.xml Tue May 28 21:18:20 2019 +0200
@@ -0,0 +1,61 @@
+<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>