3.9 Quality Values

HTTP content negotiation (Section 12) uses short "floating point" numbers to indicate the relative importance ("weight") of various negotiable parameters. A weight is normalized to a real number in the range 0 through 1, where 0 is the minimum and 1 the maximum value. If a parameter has a quality value of 0, then content with this parameter is `not acceptable' for the client. HTTP/1.1 applications MUST NOT generate more than three digits after the decimal point. User configuration of these values SHOULD also be limited in this fashion.


= ( "0" [ "." 0*3DIGIT ] ) | ( "1" [ "." 0*3("0") ] )

"Quality values" is a misnomer, since these values merely represent relative degradation in desired quality.