Module

Data.Number

Package: purescript-numbers
Repository: purescript/purescript-numbers

Functions for working with PureScripts builtin Number type.

#fromString Source

fromString :: String -> Maybe Number

Attempt to parse a Number using JavaScripts parseFloat. Returns Nothing if the parse fails or if the result is not a finite number.

Example:

> fromString "123"
(Just 123.0)

> fromString "12.34"
(Just 12.34)

> fromString "1e4"
(Just 10000.0)

> fromString "1.2e4"
(Just 12000.0)

> fromString "bad"
Nothing

Note that parseFloat allows for trailing non-digit characters and whitespace as a prefix:

> fromString "  1.2 ??"
(Just 1.2)

#nan Source

nan :: Number

Not a number (NaN).

> nan
NaN

#isNaN Source

isNaN :: Number -> Boolean

Test whether a number is NaN.

> isNaN 0.0
false

> isNaN nan
true

#infinity Source

infinity :: Number

Positive infinity. For negative infinity use (-infinity)

> infinity
Infinity

> (-infinity)
- Infinity

#isFinite Source

isFinite :: Number -> Boolean

Test whether a number is finite.

> isFinite 0.0
true

> isFinite infinity
false

> isFinite (-infinity)
false

> isFinite nan
false

#abs Source

abs :: Number -> Number

Returns the absolute value of the argument.

> x = -42.0
> sign x * abs x == x
true

#acos Source

acos :: Number -> Number

Returns the inverse cosine in radians of the argument.

> acos 0.0 == pi / 2.0
true

#asin Source

asin :: Number -> Number

Returns the inverse sine in radians of the argument.

> asin 1.0 == pi / 2.0
true

#atan Source

atan :: Number -> Number

Returns the inverse tangent in radians of the argument.

> atan 1.0 == pi / 4.0
true

#atan2 Source

atan2 :: Number -> Number -> Number

Four-quadrant tangent inverse. Given the arguments y and x, returns the inverse tangent of y / x, where the signs of both arguments are used to determine the sign of the result. If the first argument is negative, the result will be negative. The result is the angle between the positive x axis and a point (x, y).

> atan2 0.0 1.0
0.0
> atan2 1.0 0.0 == pi / 2.0
true

#ceil Source

ceil :: Number -> Number

Returns the smallest integer not smaller than the argument.

> ceil 1.5
2.0

#cos Source

cos :: Number -> Number

Returns the cosine of the argument, where the argument is in radians.

> cos (pi / 4.0) == sqrt2 / 2.0
true

#exp Source

exp :: Number -> Number

Returns e exponentiated to the power of the argument.

> exp 1.0
2.718281828459045

#floor Source

floor :: Number -> Number

Returns the largest integer not larger than the argument.

> floor 1.5
1.0

#log Source

log :: Number -> Number

Returns the natural logarithm of a number.

> log e
1.0

#max Source

max :: Number -> Number -> Number

Returns the largest of two numbers. Unlike max in Data.Ord this version returns NaN if either argument is NaN.

#min Source

min :: Number -> Number -> Number

Returns the smallest of two numbers. Unlike min in Data.Ord this version returns NaN if either argument is NaN.

#pow Source

pow :: Number -> Number -> Number

Return the first argument exponentiated to the power of the second argument.

> pow 3.0 2.0
9.0
> sqrt 42.0 == pow 42.0 0.5
true

#remainder Source

remainder :: Number -> Number -> Number

Computes the remainder after division. This is the same as JavaScript's % operator.

#(%) Source

Operator alias for Data.Number.remainder (left-associative / precedence 7)

#round Source

round :: Number -> Number

Returns the integer closest to the argument.

> round 1.5
2.0

#sign Source

sign :: Number -> Number

Returns either a positive or negative +/- 1, indicating the sign of the argument. If the argument is 0, it will return a +/- 0. If the argument is NaN it will return NaN.

> x = -42.0
> sign x * abs x == x
true

#sin Source

sin :: Number -> Number

Returns the sine of the argument, where the argument is in radians.

> sin (pi / 2.0)
1.0

#sqrt Source

sqrt :: Number -> Number

Returns the square root of the argument.

> sqrt 49.0
7.0

#tan Source

tan :: Number -> Number

Returns the tangent of the argument, where the argument is in radians.

> tan (pi / 4.0)
0.9999999999999999

#trunc Source

trunc :: Number -> Number

Truncates the decimal portion of a number. Equivalent to floor if the number is positive, and ceil if the number is negative.

ceil 1.5
2.0

#e Source

e :: Number

The base of the natural logarithm, also known as Euler's number or e.

> log e
1.0

> exp 1.0 == e
true

> e
2.718281828459045

#ln2 Source

ln2 :: Number

The natural logarithm of 2.

> log 2.0 == ln2
true

> ln2
0.6931471805599453

#ln10 Source

ln10 :: Number

The natural logarithm of 10.

> log 10.0 == ln10
true

> ln10
2.302585092994046

#log10e Source

log10e :: Number

Base 10 logarithm of e.

> 1.0 / ln10 - log10e
-5.551115123125783e-17

> log10e
0.4342944819032518

#log2e Source

log2e :: Number

The base 2 logarithm of e.

> 1.0 / ln2 == log2e
true

> log2e
1.4426950408889634

#pi Source

pi :: Number

The ratio of the circumference of a circle to its diameter.

> pi
3.141592653589793

#sqrt1_2 Source

sqrt1_2 :: Number

The square root of one half.

> sqrt 0.5 == sqrt1_2
true

> sqrt1_2
0.7071067811865476

#sqrt2 Source

sqrt2 :: Number

The square root of two.

> sqrt 2.0 == sqrt2
true

> sqrt2
1.4142135623730951

#tau Source

tau :: Number

The ratio of the circumference of a circle to its radius.

> 2.0 * pi == tau
true

> tau
6.283185307179586

Modules: Data.Number; Data.Number.Approximate; Data.Number.Format