You are looking at historical revision 14119 of this page. It may differ significantly from its current revision.

## mathh

## Documentation

Provides access to ISO C math functions in <math.h> that are not defined by the Chicken core.

### Floating-point Functions

The following procedures are provided, with their usual meaning:

`N`, `N1`, `N2` are `double`.

`O`, `P2} are {{integer`.

#### bessel-j0

#### bessel-j1

#### bessel-jn

#### bessel-jn

#### bessel-y0

#### bessel-y1

#### bessel-yn

*[procedure]*

`(bessel-j0 N) => NUMBER`

*[procedure]*

`(bessel-j1 N) => NUMBER`

*[procedure]*

`(bessel-jn O N) => NUMBER`

*[procedure]*

`(bessel-y0 N) => NUMBER`

*[procedure]*

`(bessel-y1 N) => NUMBER`

*[procedure]*

`(bessel-yn O N) => NUMBER`

The Bessel functions are prefixed by 'bessel-' to distinguish the names from common variables.

#### cosh

#### sinh

#### tanh

#### hypot

*[procedure]*

`(cosh N) => NUMBER`

*[procedure]*

`(sinh N) => NUMBER`

*[procedure]*

`(tanh N) => NUMBER`

*[procedure]*

`(hypot N1 N2) => NUMBER`

#### gamma

#### lgamma

*[procedure]*

`(gamma N) => NUMBER`

*[procedure]*

`(lgamma N) => NUMBER`

`gamma` and `lgamma` are unavailable on `Windows`.

#### log10

#### log2

#### log1p

*[procedure]*

`(log10 N) => NUMBER`

*[procedure]*

`(log2 N) => NUMBER`

*[procedure]*

`(log1p N) => NUMBER`

`log1p` is potentially inaccurate on `Windows`.

#### ldexp

#### scalbn

*[procedure]*

`(ldexp N P2) => NUMBER`

*[procedure]*

`(scalbn N P2) => NUMBER`

`scalbn` is inefficient on `Windows`.

#### make-log/base

*[procedure]*

`(make-log/base BASE) => PROCEDURE/1-NUMBER`

Returns a procedure of one argument, the logarithm function for `BASE`.

`BASE` is a `number`.

#### cbrt

*[procedure]*

`(cbrt N) => NUMBER`

Returns the cube root of `N`.

`N` is `double`.

#### nextafter

*[procedure]*

`(nextafter N M) => NUMBER`

Returns the next number `N` in the direction of `M`.

`N` and `M` are `double`.

#### fpmod

*[procedure]*

`(fpmod N M) => NUMBER`

Returns the modulus of `N` for `M`.

`N` and `M` are `double`.

#### modf

*[procedure]*

`(modf N) => (values NUMBER NUMBER)`

Returns two values, the integral and fractional components of `N`.

`N` is `double`.

#### frexp

*[procedure]*

`(frexp N) => (values NUMBER NUMBER)`

Returns two values, the fraction and the exponent components of `N`.

`N` is `double`.

#### signbit

*[procedure]*

`(signbit N) => NUMBER`

Returns `#t` when negative, `#f` otherwise.

`N` is `double`.

#### copysign

*[procedure]*

`(copysign N M) => NUMBER`

Returns `N` with same sign as `M`.

`N` and `M` are `double`.

### Float Classification

(procedure (fpclassify N))

Returns a symbol denoting the floating-point kind of `N`.

`N` is `double`.

- infinite
- nan
- normal
- subnormal
- zero
- unclassified

(procedure (fpclass N))

Returns a symbol denoting the floating-point kind of `N`.

`N` is `double`.

- positive-infinite
- negative-infinite
- quiet-nan
- signaling-nan
- positive-normal
- negative-normal
- positive-subnormal
- negative-subnormal
- positive-zero
- negative-zero
- unclassified

### Math Constants

Common constants, using 'define-constant'. As such they must be textually included.

- E
- e
- 1/E
- 1/e
- E^2
- e^2
- E^PI/4
- e^(pi/4)
- LOG2E
- log2(e)
- LOG10E
- log10(e)
- LN2
- log(2)
- LN3
- ln(3)
- LNPI
- ln(pi)
- LN10
- log(10)
- 1/LN2
- 1/ln(2)
- 1/LN10
- 1/ln(10)
- PI
- pi
- PI/2
- pi/2
- PI/4
- pi/4
- 1/PI
- 1/pi
- 2/PI
- 2/pi
- 2/SQRTPI
- 2/sqrt(pi)
- SQRTPI
- sqrt(pi)
- PI^2
- pi^2
- DEGREE
- pi/180
- SQRT2
- sqrt(2)
- 1/SQRT2
- 1/sqrt(2)
- SQRT3
- sqrt(3)
- SQRT5
- sqrt(5)
- SQRT10
- sqrt(10)
- CUBERT2
- cubert(2)
- CUBERT3
- cubert(3)
- 4THRT2
- fourthrt(2)
- GAMMA1/2
- gamma(1/2)
- GAMMA1/3
- gamma(1/3)
- GAMMA2/3
- gamma(2/3)
- PHI
- phi
- LNPHI
- ln(phi)
- 1/LNPHI
- 1/ln(phi)
- EULER
- euler
- E^EULER
- e^euler
- SIN1
- sin(1)
- COS1
- cos(1)
- ZETA3
- theta(3

## Usage

### Math functions

(require-library mathh) (import mathh)

or

(require-extension mathh)

### Math constants

(include mathh-constants)

## Examples

## Notes

## Requirements

## Bugs and Limitations

## Author

kon lovett and john cowan

## Version history

- 2.1.0
- Added 'signbit', 'copysign', 'nextafter' and 'cbrt'.
- 2.0.0
- Chicken 4 release.
`fpclass`and`fpclassify`are now part of the**mathh**extension.

## License

This code is in the public domain.