138 lines
4.0 KiB
XML
138 lines
4.0 KiB
XML
<?xml version="1.0"?>
|
|
<!--
|
|
Copyright (C) 2017 R-T Specialty, LLC.
|
|
|
|
This file is part of tame-core.
|
|
|
|
tame-core is free software: you can redistribute it and/or modify it
|
|
under the terms of the GNU Lesser General Public License as
|
|
published by the Free Software Foundation, either version 3 of the
|
|
License, or (at your option) any later version.
|
|
|
|
This program is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
-->
|
|
<package xmlns="http://www.lovullo.com/rater"
|
|
xmlns:c="http://www.lovullo.com/calc"
|
|
xmlns:t="http://www.lovullo.com/rater/apply-template"
|
|
core="true"
|
|
desc="Operations Based on Vector Length">
|
|
|
|
<import package="../base" />
|
|
<import package="../numeric/common" export="true" />
|
|
|
|
|
|
See the respective test specification for examples.
|
|
|
|
|
|
<section title="Non-empty Vectors">
|
|
\ref{_first-nonempty_} will yield the result of the first toplevel
|
|
expression that is not an empty vector.
|
|
This template yields an empty vector if no non-empty vectors are found.
|
|
|
|
<template name="_first-nonempty_"
|
|
desc="Return the first non-empty vector">
|
|
<param name="@values@" desc="List of vectors" />
|
|
|
|
|
|
<c:let>
|
|
<c:values>
|
|
<!-- avoid having to copy @values@ multiple times -->
|
|
<c:value name="_list" type="float"
|
|
desc="Result of body expression">
|
|
<c:set>
|
|
<param-copy name="@values@" />
|
|
</c:set>
|
|
</c:value>
|
|
</c:values>
|
|
|
|
|
|
<c:apply name="_first_nonempty">
|
|
<c:arg name="list">
|
|
<c:value-of name="_list" />
|
|
</c:arg>
|
|
|
|
<c:arg name="index">
|
|
<c:const value="0" desc="First element" />
|
|
</c:arg>
|
|
|
|
<c:arg name="length">
|
|
<c:length-of>
|
|
<c:value-of name="_list" />
|
|
</c:length-of>
|
|
</c:arg>
|
|
</c:apply>
|
|
</c:let>
|
|
</template>
|
|
|
|
|
|
Its helper function is \ref{_first_nonempty},
|
|
which recurses through each vector element until a non-empty vector is
|
|
encountered.
|
|
|
|
<function name="_first_nonempty"
|
|
desc="Return the first non-empty vector">
|
|
<param name="list" type="float" set="vector"
|
|
desc="List of vectors to process" />
|
|
|
|
<param name="index" type="integer"
|
|
desc="Current index (for recursion), decrementing" />
|
|
<param name="length" type="integer"
|
|
desc="Length of list" />
|
|
|
|
|
|
<c:let>
|
|
<c:values>
|
|
<c:value name="cur_len" type="integer"
|
|
desc="Length of current vector">
|
|
<c:length-of>
|
|
<c:value-of name="list" index="index" />
|
|
</c:length-of>
|
|
</c:value>
|
|
</c:values>
|
|
|
|
|
|
<c:cases>
|
|
<!-- if none were found (end of list), return empty vector -->
|
|
<c:case>
|
|
<c:when name="index">
|
|
<c:gte>
|
|
<c:value-of name="length" />
|
|
</c:gte>
|
|
</c:when>
|
|
|
|
<c:set />
|
|
</c:case>
|
|
|
|
<!-- non-empty vector, return it -->
|
|
<c:case>
|
|
<c:when name="cur_len">
|
|
<c:gt>
|
|
<c:const value="0" desc="Vector length" />
|
|
</c:gt>
|
|
</c:when>
|
|
|
|
<c:value-of name="list" index="index" />
|
|
</c:case>
|
|
|
|
<!-- vector was empty, keep going (decrement index) -->
|
|
<c:otherwise>
|
|
<c:recurse>
|
|
<c:arg name="index">
|
|
<t:inc>
|
|
<c:value-of name="index" />
|
|
</t:inc>
|
|
</c:arg>
|
|
</c:recurse>
|
|
</c:otherwise>
|
|
</c:cases>
|
|
</c:let>
|
|
</function>
|
|
</section>
|
|
</package>
|