If x or y is a finite floating-point or complex number, the comparison x=y is treated like the everyday use of equality (that is, with a reasonable relative tolerance), yielding 1 if the difference x-y falls relatively close to zero. Tolerant comparison also applies to other relations and to floor and ceiling (<. and >.); a precise definition is given in Part III under Equal (=). An arbitrary tolerance t can be specified by using the fit conjunction (!.), as in x =!.t y . The global tolerance can be queried and set using 9!:18 and 9!:19 .