鉴于相似性可能发生在字符串中的任何一点,仅仅要求它们以相同的字符集开头是不够的.例如,取这两句话(根据你的问题改编)：

Rigorous testing of the N2225 and N2226 SAS/SATA HBAs by Lenovo through the ServerProven® program ensures a high degree of confidence in storage subsystem compatibility and reliability. Providing an additional peace of mind,these controllers are covered under Lenovo warranty.
The rigorous testing of the N2225 and N2226 SAS/SATA HBAs by Lenovo through the ServerProven® program ensures a high degree of confidence in storage subsystem compatibility and reliability. Providing an additional peace of mind,these controllers are covered under Lenovo warranty.

它们非常相似,没有以相同的字符串开头.确定相似性度量的一种方法是Smith–Waterman_algorithm,有一个PHP实现可用here.

—后来编辑—

这是使用PHP内置于similar_text()的实现

/**
 * @param mixed $array          input array
 * @param int $minSimilarity    minimum similarity for an item to be removed (percentage)
 * @return array
 */
function applyFilter ($array,$minSimilarity = 90) {
    $result = [];

    foreach ($array as $outerValue) {
        $append = true;
        foreach ($result as $key => $innerValue) {
            $similarity = null;
            similar_text($innerValue,$outerValue,$similarity);
            if ($similarity >= $minSimilarity) {
                if (strlen($outerValue) > strlen($innerValue)) {
                    // always keep the longer one
                    $result[$key] = $outerValue;
                }
                $append = false;
                break;
            }
        }

        if ($append) {
            $result[] = $outerValue;
        }
    }

    return $result;
}

$test = [
    'The N2225 and N2226 SAS/SATA HBAs are low-cost,high-performance host bus adapters for high-performance connectivity between System x® servers and tape drives and RAID storage systems. The N2225 provides two x4 external mini-SAS HD connectors with eight lanes of 12 Gbps SAS. The N2226 provides four x4 external mini-SAS HD connectors with 16 lanes of 12 Gbps SAS.','The N2225 and N2226 SAS/SATA HBAs are low-cost,high-performance host bus adapters for high-performance connectivity between System x® servers and tapes drives and RAID storage systems. The N2225 provides two x4 external mini-SAS HD connectors with eight lanes of 12 Gbps SAS. The N2226 provides four x4 external mini-SAS HD connectors with 16 lanes of 12 Gbps SAS.','The N2225 and N2226 SAS/SATA HBAs support SAS data transfer rates of 3,and they enable maximum connectivity and performance in a low-profile (N2225) or full-height (N2226) form factor.','Rigorous testing of the N2225 and N2226 SAS/SATA HBAs by Lenovo through the ServerProven® program ensures a high degree of confidence in storage subsystem compatibility and reliability. Providing an additional peace of mind,these controllers are covered under Lenovo warranty.','The following tables list the compatibility information for the N2225 and N2226 SAS/SATA HBAs and System x®,and NeXtScale™ servers.','For more information about the System x servers,including older servers that support the N2225 and N2226 adapters,see the following ServerProven® website:','The following table lists the external storage systems that are currently offered by Lenovo that can be used with the N2225 and N2226 SAS/SATA HBAs in storage solutions.','The following table lists the external tape backup units that are currently offered by Lenovo that can be used with the N2225 and N2226 SAS/SATA HBAs in tape backup solutions.','For more information about the specific versions and service levels that are supported and any other prerequisites,see the ServerProven website:','The N2225 and N2226 SAS/SATA HBAs carry a one-year limited warranty. When installed in a supported System x server,the adapters assume your system’s base warranty and any Lenovo warranty upgrade.',];

var_dump(applyFilter($test));

— EOF后来编辑—

以下是Smith–Waterman_algorithm的完整工作代码：

class SmithWatermanGotoh
{
    private $gapValue;
    private $substitution;

    /**
     * Constructs a new Smith Waterman metric.
     *
     * @param gapValue
     *            a non-positive gap penalty
     * @param substitution
     *            a substitution function
     */
    public function __construct($gapValue=-0.5,$substitution=null)
    {
        if($gapValue > 0.0) throw new Exception("gapValue must be <= 0");
        //if(empty($substitution)) throw new Exception("substitution is required");
        if (empty($substitution)) $this->substitution = new SmithWatermanMatchMismatch(1.0,-2.0);
        else $this->substitution = $substitution;
        $this->gapValue = $gapValue;
    }

    public function compare($a,$b)
    {
        if (empty($a) && empty($b)) {
            return 1.0;
        }

        if (empty($a) || empty($b)) {
            return 0.0;
        }

        $maxDistance = min(mb_strlen($a),mb_strlen($b))
                * max($this->substitution->max(),$this->gapValue);
        return $this->smithWatermanGotoh($a,$b) / $maxDistance;
    }

    private function smithWatermanGotoh($s,$t)
    {
        $v0 = [];
        $v1 = [];
        $t_len = mb_strlen($t);
        $max = $v0[0] = max(0,$this->gapValue,$this->substitution->compare($s,$t,0));

        for ($j = 1; $j < $t_len; $j++) {
            $v0[$j] = max(0,$v0[$j - 1] + $this->gapValue,$j));

            $max = max($max,$v0[$j]);
        }

        // Find max
        for ($i = 1; $i < mb_strlen($s); $i++) {
            $v1[0] = max(0,$v0[0] + $this->gapValue,$i,0));

            $max = max($max,$v1[0]);

            for ($j = 1; $j < $t_len; $j++) {
                $v1[$j] = max(0,$v0[$j] + $this->gapValue,$v1[$j - 1] + $this->gapValue,$v0[$j - 1] + $this->substitution->compare($s,$j));

                $max = max($max,$v1[$j]);
            }

            for ($j = 0; $j < $t_len; $j++) {
                $v0[$j] = $v1[$j];
            }
        }

        return $max;
    }
}

class SmithWatermanMatchMismatch
{
    private $matchValue;
    private $mismatchValue;

    /**
     * Constructs a new match-mismatch substitution function. When two
     * characters are equal a score of <code>matchValue</code> is assigned. In
     * case of a mismatch a score of <code>mismatchValue</code>. The
     * <code>matchValue</code> must be strictly greater then
     * <code>mismatchValue</code>
     *
     * @param matchValue
     *            value when characters are equal
     * @param mismatchValue
     *            value when characters are not equal
     */
    public function __construct($matchValue,$mismatchValue) {
        if($matchValue <= $mismatchValue) throw new Exception("matchValue must be > matchValue");

        $this->matchValue = $matchValue;
        $this->mismatchValue = $mismatchValue;
    }

    public function compare($a,$aIndex,$b,$bIndex) {
        return ($a[$aIndex] === $b[$bIndex] ? $this->matchValue
                : $this->mismatchValue);
    }

    public function max() {
        return $this->matchValue;
    }

    public function min() {
        return $this->mismatchValue;
    }
}

/**
 * @param mixed $array          input array
 * @param int $minSimilarity    minimum similarity for an item to be removed (percentage)
 * @return array
 */
function applyFilter ($array,$minSimilarity = 90) {
    $swg = new SmithWatermanGotoh();

    $result = [];

    foreach ($array as $outerValue) {
        $append = true;
        foreach ($result as $key => $innerValue) {
            $similarity = $swg->compare($innerValue,$outerValue) * 100;
            if ($similarity >= $minSimilarity) {
                if (strlen($outerValue) > strlen($innerValue)) {
                    // always keep the longer one
                    $result[$key] = $outerValue;
                }
                $append = false;
                break;
            }
        }

        if ($append) {
            $result[] = $outerValue;
        }
    }

    return $result;
}


$test = [
    'The N2225 and N2226 SAS/SATA HBAs are low-cost,];

var_dump(applyFilter($test));

现在您只需根据需要调整$minSimilarity变量.例如,在您的情况下,如果保持默认的90％,将删除第一个元素(类似于第二个到99.86％度).但是,设置较低的值(80％)也会删除第8个元素.

希望能帮助到你！