# const class sys::Float

```sys::Obj
sys::Num
sys::Float```

`@Serializable { simple=true }`

Float is used to represent a 64-bit floating point number.

abs

` Float abs()`

Return the absolute value of this float. If this value is positive then return this, otherwise return the negation.

acos

` Float acos()`

Return the arc cosine.

approx

` Bool approx(Float r, Float? tolerance := null)`

Return if this Float is approximately equal to the given Float by the specified tolerance. If tolerance is null, then it is computed using the magnitude of the two Floats. It is useful for comparing Floats since often they lose a bit of precision during manipulation. This method is equivalent to:

```if (tolerance == null) tolerance = min(abs(this/1e6), abs(r/1e6))
(this - r).abs < tolerance```
asin

` Float asin()`

Return the arc sine.

atan

` Float atan()`

Return the arc tangent.

atan2

`static Float atan2(Float y, Float x)`

Converts rectangular coordinates (x, y) to polar (r, theta).

bits

` Int bits()`

Return 64-bit representation according IEEE 754 floating-point double format bit layout. This method is paired with `Float.makeBits`.

bits32

` Int bits32()`

Return 32-bit representation according IEEE 754 floating-point single format bit layout. This method is paired with `Float.makeBits32`.

ceil

` Float ceil()`

Returns the smallest whole number greater than or equal to this number.

clip

` Float clip(Float min, Float max)`

Clip this float between the min and max. If its less than min then return min, if its greater than max return max, otherwise return this float itself.

compare

`virtual override Int compare(Obj obj)`

Compare based on floating point value.

NaN works as follows:

• for the `<=>` operator NaN is always less than other values and equal to itself (so sort works as expected)
• for all other comparison operators anything compared against NaN is false (normal Java semanatics)

Examples:

```Float.nan <=> Float.nan  =>  0
2f <=> Float.nan         =>  1
Float.nan <=> 2f         =>  -1
2f < Float.nan           =>  false
Float.nan < 2f           =>  false
Float.nan <= Float.nan   =>  false```
cos

` Float cos()`

Return the cosine of this angle in radians.

cosh

` Float cosh()`

Return the hyperbolic cosine.

decrement

`@Operator Float decrement()`

Decrement by one. Shortcut is --a or a--.

defVal

`const static Float defVal`

Default value is 0f.

div

`@Operator Float div(Float b)`

Divide this by b. Shortcut is a/b.

divDecimal

`@Operator Decimal divDecimal(Decimal b)`

Divide this by b. Shortcut is a/b.

divInt

`@Operator Float divInt(Int b)`

Divide this by b. Shortcut is a/b.

e

`const static Float e`

Float value for e which is the base of natural logarithms.

equals

`virtual override Bool equals(Obj? obj)`

Return true if same float value. Like Java, NaN != NaN. Also see `compare`.

exp

` Float exp()`

Return e raised to this power.

floor

` Float floor()`

Returns the largest whole number less than or equal to this number.

fromStr

`static new fromStr(Str s, Bool checked := true)`

Parse a Str into a Float. Representations for infinity and not-a-number are "-INF", "INF", "NaN". This string format matches the lexical representation of Section 3.2.5 of XML Schema Part 2. If invalid format and checked is false return null, otherwise throw ParseErr.

hash

`virtual override Int hash()`

Return bits().

increment

`@Operator Float increment()`

Increment by one. Shortcut is ++a or a++.

isNaN

` Bool isNaN()`

Return if this is Float.nan. Also see `compare`.

isNegZero

` Bool isNegZero()`

Return if this is negative zero value.

log

` Float log()`

Return natural logarithm of this number.

log10

` Float log10()`

Return base 10 logarithm of this number.

makeBits

`static Float makeBits(Int bits)`

Make a Float for the specified 64-bit representation according IEEE 754 floating-point double format bit layout. This method is paired with `Float.bits`.

makeBits32

`static Float makeBits32(Int bits)`

Make a Float for the specified 32-bit representation according IEEE 754 floating-point single format bit layout. This method is paired with `Float.bits32`.

max

` Float max(Float that)`

Return the larger of this and the specified Float values.

min

` Float min(Float that)`

Return the smaller of this and the specified Float values.

minus

`@Operator Float minus(Float b)`

Subtract b from this. Shortcut is a-b.

minusDecimal

`@Operator Decimal minusDecimal(Decimal b)`

Subtract b from this. Shortcut is a-b.

minusInt

`@Operator Float minusInt(Int b)`

Subtract b from this. Shortcut is a-b.

mod

`@Operator Float mod(Float b)`

Return remainder of this divided by b. Shortcut is a%b.

modDecimal

`@Operator Decimal modDecimal(Decimal b)`

Return remainder of this divided by b. Shortcut is a%b.

modInt

`@Operator Float modInt(Int b)`

Return remainder of this divided by b. Shortcut is a%b.

mult

`@Operator Float mult(Float b)`

Multiply this with b. Shortcut is a*b.

multDecimal

`@Operator Decimal multDecimal(Decimal b)`

Multiply this with b. Shortcut is a*b.

multInt

`@Operator Float multInt(Int b)`

Multiply this with b. Shortcut is a*b.

nan

`const static Float nan`

Float value for Not-A-Number.

negInf

`const static Float negInf`

Float value for negative infinity.

negate

`@Operator Float negate()`

Negative of this. Shortcut is -a.

normNegZero

` Float normNegZero()`

If this value is negative zero then return normalized zero, otherwise return this value.

pi

`const static Float pi`

Float value for pi which is the ratio of the circumference of a circle to its diameter.

plus

`@Operator Float plus(Float b)`

Add this with b. Shortcut is a+b.

plusDecimal

`@Operator Decimal plusDecimal(Decimal b)`

Add this with b. Shortcut is a+b.

plusInt

`@Operator Float plusInt(Int b)`

Add this with b. Shortcut is a+b.

posInf

`const static Float posInf`

Float value for positive infinity.

pow

` Float pow(Float pow)`

Return this value raised to the specified power.

random

`static Float random()`

Generate a random float between 0.0 inclusive and 1.0 exclusive. Also see `Int.random`, `Range.random`, `List.random`, and `Random`.

round

` Float round()`

Returns the nearest whole number to this number.

sin

` Float sin()`

Return sine of this angle in radians.

sinh

` Float sinh()`

Return hyperbolic sine.

sqrt

` Float sqrt()`

Return square root of this value.

tan

` Float tan()`

Return tangent of this angle in radians.

tanh

` Float tanh()`

Return hyperbolic tangent.

toCode

` Str toCode()`

Get this Float as a Fantom code literal.

toDegrees

` Float toDegrees()`

Convert this angle in radians to an angle in degrees.

toLocale

` Str toLocale(Str? pattern := null, Locale locale := Locale.cur())`

Format this floating point number for the current locale. If pattern is null, then the locale's default pattern is used. Also see `Num.localeDecimal`, `Num.localeGrouping`, etc.

The pattern format:

```#   optional digit
0   required digit
.   decimal point
,   grouping separator (only last one before decimal matters)```

Examples:

```12345.786f.toLocale("#,###.0")  =>  12,345.8
7.1234f.toLocale("#.000")       =>  7.123
0.1234f.toLocale("#.000")       =>  .123
0.1234f.toLocale("0.00")        =>  0.12
70.12f.toLocale("0.0000")       =>  70.1200```
` Float toRadians()`
`virtual override Str toStr()`