# tablepress/3.4/libraries/vendor/PhpSpreadsheet/Calculation/LookupRef/LookupBase.php

TablePress – Tables in WordPress made easy, version 3.4. 71 lines.

- Page: https://pluginprobe.com/plugins/tablepress/3.4/code/libraries/vendor/PhpSpreadsheet/Calculation/LookupRef/LookupBase.php
- Raw: https://pluginprobe.com/plugins/tablepress/3.4/raw/libraries/vendor/PhpSpreadsheet/Calculation/LookupRef/LookupBase.php
- Modified: 2025-08-26T04:06:14+00:00

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```php
<?php

namespace TablePress\PhpOffice\PhpSpreadsheet\Calculation\LookupRef;

use TablePress\PhpOffice\PhpSpreadsheet\Calculation\Exception;
use TablePress\PhpOffice\PhpSpreadsheet\Calculation\Information\ExcelError;

abstract class LookupBase
{
	/**
				 * @param mixed $lookupArray
				 */
				protected static function validateLookupArray($lookupArray): void
	{
		if (!is_array($lookupArray)) {
			throw new Exception(ExcelError::REF());
		}
	}

	/**
	 * @param mixed[] $lookupArray
	 * @param float|int|string $index_number number >= 1
	 */
	protected static function validateIndexLookup(array $lookupArray, $index_number): int
	{
		// index_number must be a number greater than or equal to 1.
		// Excel results are inconsistent when index is non-numeric.
		// VLOOKUP(whatever, whatever, SQRT(-1)) yields NUM error, but
		// VLOOKUP(whatever, whatever, cellref) yields REF error
		//   when cellref is '=SQRT(-1)'. So just try our best here.
		// Similar results if string (literal yields VALUE, cellRef REF).
		if (!is_numeric($index_number)) {
			throw new Exception(ExcelError::throwError($index_number));
		}
		if ($index_number < 1) {
			throw new Exception(ExcelError::VALUE());
		}

		// index_number must be less than or equal to the number of columns in lookupArray
		if (empty($lookupArray)) {
			throw new Exception(ExcelError::REF());
		}

		return (int) $index_number;
	}

	protected static function checkMatch(
		bool $bothNumeric,
		bool $bothNotNumeric,
		bool $notExactMatch,
		int $rowKey,
		string $cellDataLower,
		string $lookupLower,
		?int $rowNumber
	): ?int {
		// remember the last key, but only if datatypes match
		if ($bothNumeric || $bothNotNumeric) {
			// Spreadsheets software returns first exact match,
			// we have sorted and we might have broken key orders
			// we want the first one (by its initial index)
			if ($notExactMatch) {
				$rowNumber = $rowKey;
			} elseif (($cellDataLower == $lookupLower) && (($rowNumber === null) || ($rowKey < $rowNumber))) {
				$rowNumber = $rowKey;
			}
		}

		return $rowNumber;
	}
}

```