<?php
 
define(
 
    'FLOAT',
 
    ';\s*?q=
    (1|0                            # 1 or 0
        (\.                         # Literal dot
            ([0-9]{1,2}[1-9]|       # One or Two Zeroes followed by 1...9 -OR-
             [0-9][1-9][0-9]?|      # Zero followed by 1...9, followed by an optional 0...9 -OR-
             [1-9]                  # 1...9 followed by:
                ([0-9]{0,2}|        # None and up to Two 0...9 -OR-
                 [0-9][1-9]|        # 0...9 and then followed by 1...9 -OR-
                 [1-9]{1,3}         # 1...9 once and up to three
                )
             )
        )?                          # All this is optional, and refers to float range
    )'
);
 
preg_match( sprintf( '@(?<params>%s)@x', FLOAT ), ';q=0.3444', $matches );
 
var_dump( $matches );

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