Struct Decimal 

pub struct Decimal { /* private fields */ }

An arbitrary-precision Decimal type with a distinct representation of negative zero (-0).

A Decimal can be thought of as a (coefficient, exponent) pair, and its value can be calculated using the formula coefficient * 10^exponent.

use ion_rs::{Int, Decimal, UInt};
use ion_rs::decimal::Sign;
// Equivalent to: 1225 * 10^-2, or 12.25
let decimal = Decimal::new(1225, -2);
// The coefficient can be viewed as a sign/magnitude pair...
assert_eq!(decimal.coefficient().sign(), Sign::Positive);
assert_eq!(decimal.coefficient().magnitude(), UInt::from(1225u64));
// ...or, if it is not negative zero, by converting it into an Int.
let coefficient: Int = decimal.coefficient().try_into().expect("`decimal` is not negative zero");
assert_eq!(coefficient, Int::from(1225));

assert_eq!(decimal.exponent(), -2);

Implementations

impl Decimal

pub const ZERO: Decimal

pub const NEGATIVE_ZERO: Decimal

pub fn new<C: Into<Coefficient>, E: Into<i64>>( coefficient: C, exponent: E, ) -> Decimal

Constructs a new Decimal with the provided components. The value of the decimal is: coefficient * 10^exponent

pub fn coefficient(&self) -> Coefficient

Returns this Decimal’s coefficient.

pub fn exponent(&self) -> i64

Returns this Decimal’s exponent.

pub fn scale(&self) -> i64

Returns scale of the Decimal value If zero or positive, a scale indicates the number of digits to the right of the decimal point. If negative, the unscaled value of the number is multiplied by ten to the power of the negation of the scale. For example, a scale of -3 means the unscaled value is multiplied by 1000.

pub fn precision(&self) -> u64

Returns the number of digits in the non-scaled integer representation of the decimal.

pub fn negative_zero() -> Decimal

Constructs a Decimal with the value -0d0. This is provided as a convenience method because Rust will ignore a unary minus when it is applied to an zero literal (-0).

pub fn negative_zero_with_exponent(exponent: i64) -> Decimal

Constructs a Decimal with a coefficient of -0 and the specified exponent. This function is provided as a convenience method because Rust will ignore a unary minus when it is applied to a zero literal (-0).

pub fn is_zero(&self) -> bool

Returns true if this Decimal is a zero of any sign or exponent.

pub fn is_less_than_zero(&self) -> bool

Returns true if this Decimal’s coefficient has a negative sign AND a magnitude greater than zero. Otherwise, returns false. (Negative zero returns false.)

pub fn trunc(&self) -> Decimal

Returns the integer part of self. This means that non-integer numbers are always truncated towards zero, maintaining the sign of the original coefficient.

pub fn fract(&self) -> Decimal

Returns the fractional part of self. Values with no fractional component will return zero maintaining the sign of the original coefficient.

Trait Implementations

impl Clone for Decimal

fn clone(&self) -> Decimal

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Decimal

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Display for Decimal

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for Decimal

impl From<Decimal> for Value

fn from(decimal_val: Decimal) -> Self

Converts to this type from the input type.

impl From<Int> for Decimal

fn from(value: Int) -> Self

Converts to this type from the input type.

impl From<i8> for Decimal

fn from(value: i8) -> Self

Converts to this type from the input type.

impl From<i16> for Decimal

fn from(value: i16) -> Self

Converts to this type from the input type.

impl From<i32> for Decimal

fn from(value: i32) -> Self

Converts to this type from the input type.

impl From<i64> for Decimal

fn from(value: i64) -> Self

Converts to this type from the input type.

impl From<isize> for Decimal

fn from(value: isize) -> Self

Converts to this type from the input type.

impl From<u8> for Decimal

fn from(value: u8) -> Self

Converts to this type from the input type.

impl From<u16> for Decimal

fn from(value: u16) -> Self

Converts to this type from the input type.

impl From<u32> for Decimal

fn from(value: u32) -> Self

Converts to this type from the input type.

impl From<u64> for Decimal

fn from(value: u64) -> Self

Converts to this type from the input type.

impl From<usize> for Decimal

fn from(value: usize) -> Self

Converts to this type from the input type.

impl Ord for Decimal

fn cmp(&self, other: &Self) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for Decimal

fn eq(&self, other: &Self) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd for Decimal

fn partial_cmp(&self, other: &Self) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl TryFrom<Element> for Decimal

type Error = ConversionOperationError<Element, Decimal>

The type returned in the event of a conversion error.

fn try_from(element: Element) -> ConversionOperationResult<Element, Decimal>

Performs the conversion.

impl TryFrom<f32> for Decimal

type Error = IonError

The type returned in the event of a conversion error.

fn try_from(value: f32) -> Result<Self, Self::Error>

Performs the conversion.

impl TryFrom<f64> for Decimal

fn try_from(value: f64) -> Result<Self, Self::Error>

Attempts to create a Decimal from an f64. Returns an Error if the f64 being converted is a special value, including:

• Infinity
• Negative infinity
• NaN (not-a-number)

Otherwise, returns Ok.

Because Decimal can represent negative zero, f64::neg_zero() IS supported.

NOTE: While the resulting decimal will be a very close approximation of the original f64’s value, this is an inherently lossy operation. Floating point values do not encode a precision. When converting an f64 to a Decimal, a precision for the new Decimal must be chosen somewhat arbitrarily. Do NOT rely on the precision of the resulting Decimal. This implementation may change without notice.

type Error = IonError

The type returned in the event of a conversion error.