$re = '/^text\t([\d.\h]+)$/mu';
$str = 'text 16.11 19.22 21.33
text 17.11 23.22 25.33 27.55
text 18.11 26.22';
$subst = "array('test'=>'text', 'prices'=>[$1]);";
$result = preg_replace($re, $subst, $str);
echo "The result of the substitution is ".$result;
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php