# Module `Owl_const`

Metric system: CGS, MKS, SI, and physical constants.

Values of physical constants CGS < MKS < SI. Read wikipedia on CGS and SI system for more details.

International System of Units (French: Système international d'unités, SI), historically also called the MKSA system of units for metre–kilogram–second–ampere.

The SI system of units extends the MKS system and has 7 base units, by expressing any measurement of physical quantities using fundamental units of Length, Mass, Time, Electric Current, Thermodynamic Temperature, Amount of substance and Luminous Intensity, which are Metre, Kilogram, Second, Ampere, Kelvin, Mole and Candela respectively.

###### Maths constants
`val e : float`

e = 2.718281828459045235360287471352662498

`val euler : float`

euler = 0.577215664901532860606512090082402431

`val log2e : float`

log2e = 1.442695040888963407359924681001892137

`val log10e : float`

log10e = 0.434294481903251827651128918916605082

`val loge2 : float`

loge2 = 0.693147180559945309417232121458176568

`val loge10 : float`

loge10 = 2.302585092994045684017991454684364208

`val logepi : float`

logepi = 1.144729885849400174143427351353058711

`val sqrt1_2 : float`

sqrt1_2 = 0.707106781186547524400844362104849039

`val sqrt2 : float`

sqrt2 = 1.414213562373095048801688724209698079

`val sqrt3 : float`

sqrt3 = 1.732050807568877293527446341505872366

`val sqrtpi : float`

sqrtpi = 1.772453850905516027298167483341145182

`val pi : float`

pi = 3.141592653589793238462643383279502884

`val pi2 : float`

pi2 = 6.283185307179586476925286766559005768

`val pi4 : float`

pi4 = 12.56637061435917295385057353311801153

`val pi_2 : float`

pi_2 = 1.570796326794896619231321691639751442

`val pi_4 : float`

pi_4 = 0.785398163397448309615660845819875721

`val eps : float`

eps = 1e-15

###### Constants depending on Bigarray kind
`val zero : ( 'a, 'b ) Stdlib.Bigarray.kind -> 'a`

`zero kind` returns value zero of the given number type `kind`.

`val one : ( 'a, 'b ) Stdlib.Bigarray.kind -> 'a`

`one kind` returns value one of the given number type `kind`.

`val neg_one : ( 'a, 'b ) Stdlib.Bigarray.kind -> 'a`

`neg_one kind` returns negative one of the given number type `kind`.

`val pos_inf : ( 'a, 'b ) Stdlib.Bigarray.kind -> 'a`

`pos_inf kind` returns positive infinity of the given number type `kind`.

`val neg_inf : ( 'a, 'b ) Stdlib.Bigarray.kind -> 'a`

`neg_inf kind` returns negative infinity of the given number type `kind`.

`val min_float32 : float`

Miminum value of single precision float number, i.e. ~-.340282346638528859811704183484516925440.0

`val max_float32 : float`

Maximum value of single precision float number, i.e. 340282346638528859811704183484516925440.0

`val min_float64 : float`

Miminum value of double precision float number.

`val max_float64 : float`

Maximum value of double precision float number.

###### Unit prefixes
`module Prefix : sig ... end`
###### SI: International System of Units
`module SI : sig ... end`
###### MKS: MKS system of units
`module MKS : sig ... end`
###### CGS: Centimetre–gram–second system of units
`module CGS : sig ... end`
###### CGSM: Unit Systems in Electromagnetism
`module CGSM : sig ... end`