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<?php function combineColumns(array $row, $separator) // {{{ { $combined = array(); foreach ($row as $key => $value) { if (false !== strpos($key, $separator)) { $parts = explode($separator, $key); $pkey = array_pop($parts); $ptr = &$combined; while (null !== ($part = array_shift($parts))) { if (!isset($ptr[$part]) || !is_array($ptr[$part])) { $ptr[$part] = array(); } $ptr = &$ptr[$part]; } $ptr[$pkey] = $value; } else { $combined[$key] = $value; } } } print_r(combineColumns(array( 'A' => 1, 'B_C' => 2, 'B_D_A' => 3, 'D_K_F' => 4, ), '__'));

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