Note: the result of this function is platform-dependent, so using it in syntax transformers can lead to platform-dependent bytecode files. See also fixnum-for-every-system? .

procedure
(flonum? v)→boolean?
v:any/c

Return #t if v is a flonum, #f otherwise.

procedure
( double-flonum? v)→boolean?
v:any/c

Identical to flonum? .

procedure
(single-flonum? v)→boolean?
v:any/c

Return #t if v is a single-flonum (i.e., a single-precision floating-point number), #f otherwise.

procedure
(single-flonum-available? )→boolean?

Returns #t if single-flonums are supported on the current platform, #f otherwise.

Currently, single-flonum-available? produces #t when (system-type 'vm) produces 'racket, and single-flonum-available? produces #f otherwise.

If the result is #f, then single-flonum? also produces #f for all arguments.

Added in version 7.3.0.5 of package base.

procedure
(zero? z)→boolean?
z:number?

Returns (= 0z).

Examples:

> (zero? 0)

#t
> (zero? -0.0)

#t

procedure
(positive? x)→boolean?
x:real?

Returns (> x0).

Examples:

> (positive? 10)

#t
> (positive? -10)

#f
> (positive? 0.0)

#f

procedure
(negative? x)→boolean?
x:real?

Returns (< x0).

Examples:

> (negative? 10)

#f
> (negative? -10)

#t
> (negative? -0.0)

#f

procedure
(even? n)→boolean?
n:integer?

Returns (zero? (modulo n2)).

Examples:

> (even? 10.0)

#t
> (even? 11)

#f
> (even? +inf.0)

even?: contract violation

expected: integer?

given: +inf.0

procedure
(odd? n)→boolean?
n:integer?

Returns (not (even? n)).

Examples:

> (odd? 10.0)

#f
> (odd? 11)

#t
> (odd? +inf.0)

odd?: contract violation

expected: integer?

given: +inf.0

procedure
(exact? z)→boolean?
z:number?

Returns #t if z is an exact number, #f otherwise.

Examples:

> (exact? 1)

#t
> (exact? 1.0)

#f

procedure
(inexact? z)→boolean?
z:number?

Returns #t if z is an inexact number, #f otherwise.

Examples:

> (inexact? 1)

#f
> (inexact? 1.0)

#t

procedure
(inexact->exact z)→exact?
z:number?

Coerces z to an exact number. If z is already exact, it is returned. If z is +inf.0, -inf.0, +nan.0, +inf.f, -inf.f, or +nan.f, then the exn:fail:contract exception is raised.

Examples:

> (inexact->exact 1)

1
> (inexact->exact 1.0)

1

procedure
(exact->inexact z)→inexact?
z:number?

Coerces z to an inexact number. If z is already inexact, it is returned.

Examples:

> (exact->inexact 1)

1.0
> (exact->inexact 1.0)

1.0

procedure
(real->single-flonum x)→single-flonum?
x:real?

Coerces x to a single-precision floating-point number. If x is already a single-precision floating-point number, it is returned.

procedure
(real->double-flonum x)→flonum?
x:real?

Coerces x to a double-precision floating-point number. If x is already a double-precision floating-point number, it is returned.

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