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float

float

float -- floating point values


float is the abstract parent of concrete floating point features such as
f32 or f64.

Value Constructors

§
:
Any
 is
 
[Inherited from  numeric]
absolute value using `|a|` built from a `prefix |` and `postfix |` as an operator
alias of `a.abs`

Due to the low precedence of `|`, this works also on expressions like `|a-b|`, even
with spaces `| a-b |`, `|a - b|`, `| a-b|` or `|a-b |`.

Nesting, however, does not work, e.g, `| - |a| |`, this requires parenthese `|(- |a|)|`.

NYI: CLEANUP: Due to #3081, we need `postfix |` as the first operation, should be
`prefix |` first

Functions

§
:
Any
 => 
numeric.this 
[Inherited from  numeric]
absolute value
convert a float value to i32 dropping any fraction.
the value must be in the range of i32
convert a float value to i64 dropping any fraction.
the value must be in the range of i64
§
:
Any
 => 
String 
[Inherited from  Any]
create a String from this instance. Unless redefined, `a.as_string` will
create `"instance[T]"` where `T` is the dynamic type of `a`
§
:
Any
 => 
u8 
[Inherited from  numeric]
this numeric value as an u8
ceiling: the smallest integer greater or equal to this
§
:
Any
 => 
Type 
[Inherited from  Any]
Get the dynamic type of this instance. For value instances `x`, this is
equal to `type_of x`, but for `x` with a `ref` type `x.dynamic_type` gives
the actual runtime type, while `type_of x` results in the static
compile-time type.

There is no dynamic type of a type instance since this would result in an
endless hierachy of types. So for Type values, dynamic_type is redefined
to just return Type.type.
the normalized exponent of this float
the biased exponent of this float
does this float value fit into an i64? This is redefined by children
of float that support `as_i64`.
§
:
Any
 => 
bool 
[Inherited from  numeric]
does this numeric value fit into an u8? This is redefined by children
of numeric that support `as_u8`.
floor: the greatest integer lower or equal to this
§(other numeric.this)
:
Any
 => 
numeric.this 
[Inherited from  numeric]
basic operations: 'infix %' (division remainder)
§(other numeric.this)
:
Any
 => 
bool 
[Inherited from  numeric]
§(other numeric.this)
:
Any
 => 
numeric.this 
[Inherited from  numeric]
basic operations: 'infix *' (multiplication)
§(other numeric.this)
:
Any
 => 
bool 
[Inherited from  numeric]
§(other numeric.this)
:
Any
 => 
numeric.this 
[Inherited from  numeric]
basic operations: 'infix **' (exponentiation)
§(other numeric.this)
:
Any
 => 
bool 
[Inherited from  numeric]
§(other numeric.this)
:
Any
 => 
numeric.this 
[Inherited from  numeric]
§(other numeric.this)
:
Any
 => 
numeric.this 
[Inherited from  numeric]
§(other numeric.this)
:
Any
 => 
numeric.this 
[Inherited from  numeric]
basic operations: 'infix +' (addition)
§(other numeric.this)
:
Any
 => 
bool 
[Inherited from  numeric]
§(other numeric.this)
:
Any
 => 
numeric.this 
[Inherited from  numeric]
§(other numeric.this)
:
Any
 => 
numeric.this 
[Inherited from  numeric]
basic operations: 'infix -' (subtraction)
§(other numeric.this)
:
Any
 => 
bool 
[Inherited from  numeric]
§(other numeric.this)
:
Any
 => 
numeric.this 
[Inherited from  numeric]
§(other numeric.this)
:
Any
 => 
numeric.this 
[Inherited from  numeric]
basic operations: 'infix /' (division)
§(other numeric.this)
:
Any
 => 
bool 
[Inherited from  numeric]
comparison

This provides comparison operators using IEEE semantics.

type.equality and type.lteq should be used for equivalence relations
and total ordering in the mathematical sense.
is `this` contained in `Set` `s`?

This should usually be called using type inference as in

my_set := set_of ["A","B","C"]
say ("B" ∈ my_set)
say ("D" ∈ my_set)
is `this` not contained in `Set` `s`?

This should usually be called using type inference as in

my_set := set_of ["A","B","C"]
say ("B" ∉ my_set)
say ("D" ∉ my_set)
§
:
Any
 => 
bool 
[Inherited from  numeric]
is the bit denoting the sign of the number set?
this is different from smaller than zero since
there is +0, -0, NaN, etc. in floating point numbers.
§
:
Any
 => 
bool 
[Inherited from  numeric]
the normalized mantissa of this float
§
:
Any
 => 
String 
[Inherited from  Type]
name of this type, including type parameters, e.g. 'option (list i32)'.
§
:
Any
 => 
String 
[Inherited from  Any]
convenience prefix operator to create a string from a value.

This permits usage of `$` as a prefix operator in a similar way both
inside and outside of constant strings: $x and "$x" will produce the
same string.
§
:
Any
 => 
numeric.this 
[Inherited from  numeric]
basic operations: 'prefix +' (identity)
§
:
Any
 => 
bool 
[Inherited from  numeric]
preconditions for basic operations: true if the operation's result is
representable and defined for the given values

default implementations all return `true` such that children have to
redefine these only for partial operations such as those resulting in
an overflow or that are undefined like a division by zero for most
types.
§
:
Any
 => 
numeric.this 
[Inherited from  numeric]
basic operations: 'prefix -' (negation)
§
:
Any
 => 
bool 
[Inherited from  numeric]
overflow checking operations
§
:
Any
 => 
numeric.this 
[Inherited from  numeric]
saturating operations
round floating point number
ties to away (0.5 => 1; -0.5 => -1; etc.)

NYI this could be made faster, see here:
https://cs.opensource.google/go/go/+/refs/tags/go1.18.1:src/math/floor.go;l=79
§
:
Any
 => 
i32 
[Inherited from  numeric]
sign function resulting in `-1`/`0`/`+1` depending on whether `numeric.this`
is less than, equal or larger than zero
true when the absolute value
is smaller than 0.001
or greater than 9_999_999

Value Types

§
:
Any
 is
 
[Inherited from  numeric]
absolute value using `|a|` built from a `prefix |` and `postfix |` as an operator
alias of `a.abs`

Due to the low precedence of `|`, this works also on expressions like `|a-b|`, even
with spaces `| a-b |`, `|a - b|`, `| a-b|` or `|a-b |`.

Nesting, however, does not work, e.g, `| - |a| |`, this requires parenthese `|(- |a|)|`.

NYI: CLEANUP: Due to #3081, we need `postfix |` as the first operation, should be
`prefix |` first

Type Features

§(val float.this.type)
:
Any
 is
§(val float.this.type)
:
Any
 is
§(val float.this.type)
:
Any
 is
§(val float.this.type)
:
Any
 is
§(val float.this.type)
:
Any
 is
§(y float.this.type, x float.this.type)
:
Any
 is
§(val float.this.type)
:
Any
 is
number of bytes required to store this value
§(val float.this.type)
:
Any
 is
§(val float.this.type)
:
Any
 is
§(a float.this.type, b float.this.type)
:
Any
 is
equality

This provides an equivalence relation in the mathematical
sense and therefore breaks the IEEE semantics. infix = should
be used for IEEE semantics.

The equivalence relation is provided by the usual comparison
of floating-point numbers, with the definition of NaN = NaN.
§(val float.this.type)
:
Any
 is
the `val`-th power of ℇ
i.e. ℇᵛᵃˡ
number of bits used for exponent
convert an i64 value to a floating point value

if the value cannot be represented exactly, the result is either
the nearest higher or nearest lower value
§(v u32)
:
Any
 is
 
[Inherited from  numeric]
the value corresponding to v in whatever integer implementation we have,
maximum in case of overflow
§(a property.hashable.this.type)
:
Any
 is
 
[Inherited from  hashable]
create hash code for this instance

This should satisfy the following condition:

(T.equality a b) : (T.hash_code a = T.hash_code b)
infinity
§(val float.this.type)
:
Any
 is
is not a number?
§(val float.this.type)
:
Any
 is
logarithm with base ℇ
§(base float.this.type, val float.this.type)
:
Any
 is
logarithm with base `base`
§(a float.this.type, b float.this.type)
:
Any
 is
total order

This provides a total order in the mathematical sense and
therefore breaks the IEEE semantics. infix <= should be
used for IEEE semantics.

The total order is provided by the usual comparison of
floating-point numbers, with the definition that NaN <= x,
for any x (including x = NaN).
the amount of bits that are used to encode the mantissa
not a number
§
:
Any
 is
 
[Inherited from  numeric]
identity element for 'infix *'
monoid of numeric with infix * operation. Will create product of all elements
it is applied to.
monoid of numeric with infix *^ operation. Will create product of all elements
it is applied to, stopping at max/min value in case of overflow.
non signaling not a number
number of bits used for mantissa,
including leading '1' that is not actually stored
§(val float.this.type)
:
Any
 is
§(val float.this.type)
:
Any
 is
number of bits required to store this value
§(val float.this.type)
:
Any
 is
square root alias
§(val float.this.type)
:
Any
 is
square root
monoid of numeric with infix + operation. Will create sum of all elements it
is applied to.
monoid of numeric with infix +^ operation. Will create sum of all elements it
is applied to, stopping at max/min value in case of overflow.
§(val float.this.type)
:
Any
 is
§(val float.this.type)
:
Any
 is
§
:
Any
 is
 
[Inherited from  numeric]
the constant '10' in whatever integer implementation we have, maximum in case of overflow
§
:
Any
 is
 
[Inherited from  numeric]
the constant '2' in whatever integer implementation we have, maximum in case of overflow
§
:
Any
 is
 
[Inherited from  Any]
Get a type as a value.

This is a feature with the effect equivalent to Fuzion's `expr.type` call tail.
It is recommended to use `expr.type` and not `expr.type_value`.

`type_value` is here to show how this can be implemented and to illustrate the
difference to `dynamic_type`.
§
:
Any
 is
 
[Inherited from  numeric]
identity element for 'infix +'
pi 3.14...
eulers number 2.72..