TDoG-Skin/vendor/hoa/compiler/Llk/Sampler/Uniform.php
2024-08-17 19:13:54 +08:00

303 lines
9.1 KiB
PHP
Executable File
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

<?php
/**
* Hoa
*
*
* @license
*
* New BSD License
*
* Copyright © 2007-2017, Hoa community. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name of the Hoa nor the names of its contributors may be
* used to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS AND CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
namespace Hoa\Compiler\Llk\Sampler;
use Hoa\Compiler;
use Hoa\Math;
use Hoa\Visitor;
/**
* Class \Hoa\Compiler\Llk\Sampler\Uniform.
*
* This generator aims at producing random and uniform a sequence of a fixed
* size. We use the recursive method to count all possible sub-structures of
* size n. The counting helps to compute cumulative distribution functions,
* which guide the exploration.
* Repetition unfolding: upper bound of + and * is set to n.
*
* @copyright Copyright © 2007-2017 Hoa community
* @license New BSD License
*/
class Uniform extends Sampler
{
/**
* Data (pre-computing).
*
* @var array
*/
protected $_data = [];
/**
* Bound.
*
* @var int
*/
protected $_length = 5;
/**
* Construct a generator.
*
* @param \Hoa\Compiler\Llk\Parser $compiler Compiler/parser.
* @param \Hoa\Visitor\Visit $tokenSampler Token sampler.
*/
public function __construct(
Compiler\Llk\Parser $compiler,
Visitor\Visit $tokenSampler,
$length = 5
) {
parent::__construct($compiler, $tokenSampler);
foreach ($this->_rules as $name => $_) {
$this->_data[$name] = [];
}
$this->setLength($length);
$this->_sampler = new Math\Sampler\Random();
return;
}
/**
* The random and uniform algorithm.
*
* @param \Hoa\Compiler\Llk\Rule $rule Rule to start.
* @param int $n Size.
* @return string
*/
public function uniform(Compiler\Llk\Rule $rule = null, $n = -1)
{
if (null === $rule && -1 === $n) {
$rule = $this->_rules[$this->_rootRuleName];
$n = $this->getLength();
}
$data = &$this->_data[$rule->getName()][$n];
$computed = $data['n'];
if (0 === $n || 0 === $computed) {
return null;
}
if ($rule instanceof Compiler\Llk\Rule\Choice) {
$children = $rule->getChildren();
$stat = [];
foreach ($children as $c => $child) {
$stat[$c] = $this->_data[$child][$n]['n'];
}
$i = $this->_sampler->getInteger(1, $computed);
for ($e = 0, $b = $stat[$e], $max = count($stat) - 1;
$e < $max && $i > $b;
$b += $stat[++$e]);
return $this->uniform($this->_rules[$children[$e]], $n);
} elseif ($rule instanceof Compiler\Llk\Rule\Concatenation) {
$children = $rule->getChildren();
$out = null;
= $data['Γ'];
$γ = [$this->_sampler->getInteger(0, count() - 1)];
foreach ($children as $i => $child) {
$out .= $this->uniform($this->_rules[$child], $γ[$i]);
}
return $out;
} elseif ($rule instanceof Compiler\Llk\Rule\Repetition) {
$out = null;
$stat = &$data['xy'];
$child = $this->_rules[$rule->getChildren()];
$b = 0;
$i = $this->_sampler->getInteger(1, $computed);
foreach ($stat as $α => $st) {
if ($i <= $b += $st['n']) {
break;
}
}
= &$st['Γ'];
$γ = &[$this->_sampler->getInteger(0, count() - 1)];
for ($j = 0; $j < $α; ++$j) {
$out .= $this->uniform($child, $γ[$j]);
}
return $out;
} elseif ($rule instanceof Compiler\Llk\Rule\Token) {
return $this->generateToken($rule);
}
return null;
}
/**
* Recursive method applied to our problematic.
*
* @param \Hoa\Compiler\Llk\Rule $rule Rule to start.
* @param int $n Size.
* @return int
*/
public function count(Compiler\Llk\Rule $rule = null, $n = -1)
{
if (null === $rule || -1 === $n) {
return 0;
}
$ruleName = $rule->getName();
if (isset($this->_data[$ruleName][$n])) {
return $this->_data[$ruleName][$n]['n'];
}
$this->_data[$ruleName][$n] = ['n' => 0];
$out = &$this->_data[$ruleName][$n]['n'];
$rule = $this->_rules[$ruleName];
if ($rule instanceof Compiler\Llk\Rule\Choice) {
foreach ($rule->getChildren() as $child) {
$out += $this->count($this->_rules[$child], $n);
}
} elseif ($rule instanceof Compiler\Llk\Rule\Concatenation) {
$children = $rule->getChildren();
= new Math\Combinatorics\Combination\Gamma(
count($children),
$n
);
$this->_data[$ruleName][$n]['Γ'] = [];
$handle = &$this->_data[$ruleName][$n]['Γ'];
foreach ( as $γ) {
$oout = 1;
foreach ($γ as $α => $_γ) {
$oout *= $this->count($this->_rules[$children[$α]], $_γ);
}
if (0 !== $oout) {
$handle[] = $γ;
}
$out += $oout;
}
} elseif ($rule instanceof Compiler\Llk\Rule\Repetition) {
$this->_data[$ruleName][$n]['xy'] = [];
$handle = &$this->_data[$ruleName][$n]['xy'];
$child = $this->_rules[$rule->getChildren()];
$x = $rule->getMin();
$y = $rule->getMax();
if (-1 === $y) {
$y = $n;
} else {
$y = min($n, $y);
}
if (0 === $x && $x === $y) {
$out = 1;
} else {
for ($α = $x; $α <= $y; ++$α) {
$ut = 0;
$handle[$α] = ['n' => 0, 'Γ' => []];
= new Math\Combinatorics\Combination\Gamma($α, $n);
foreach ( as $γ) {
$oout = 1;
foreach ($γ as => $_γ) {
$oout *= $this->count($child, $_γ);
}
if (0 !== $oout) {
$handle[$α]['Γ'][] = $γ;
}
$ut += $oout;
}
$handle[$α]['n'] = $ut;
$out += $ut;
}
}
} elseif ($rule instanceof Compiler\Llk\Rule\Token) {
$out = Math\Util::δ($n, 1);
}
return $out;
}
/**
* Set upper-bound, the maximum data length.
*
* @param int $length Length.
* @return int
* @throws \Hoa\Compiler\Exception
*/
public function setLength($length)
{
if (0 >= $length) {
throw new Exception(
'Length must be greater than 0, given %d.',
0,
$length
);
}
$old = $this->_length;
$this->_length = $length;
$this->count(
$this->_compiler->getRule($this->_rootRuleName),
$length
);
return $old;
}
/**
* Get upper-bound.
*
* @return int
*/
public function getLength()
{
return $this->_length;
}
}