Struct Dec

pub struct Dec(pub I256);

A 256 bit number with POS_DECIMAL_PRECISION number of Dec places.

To be precise, an instance X of this type should be interpreted as the Dec X * 10 ^ (-POS_DECIMAL_PRECISION)

Tuple Fields

0: I256

Implementations

impl Dec

pub fn trunc_div(&self, rhs: &Dec) -> Option<Dec>

Performs division with truncation.

This method divides self by rhs (right-hand side) and truncates the result to POS_DECIMAL_PRECISION decimal places. Truncation here means that any fractional part of the result that exceeds POS_DECIMAL_PRECISION is discarded.

Breakdown of the algorithm

The division is performed in the following way:

1. The absolute values of the numerator and denominator are used for the division.
2. The result is calculated to a fixed precision defined by POS_DECIMAL_PRECISION.
3. If either the numerator or denominator (but not both) is negative, the result is negated.
4. If the division is impossible (e.g., division by zero or overflow), None is returned.

Example

use namada_core::dec::Dec;

let x = Dec::new(3, 1).unwrap(); // Represents 0.3
let y = Dec::new(2, 1).unwrap(); // Represents 0.2
let result = x.trunc_div(&y).unwrap();
assert_eq!(result, Dec::new(15, 1).unwrap()); // Result is 1.5 truncated to 1 decimal place

Arguments

• rhs: The right-hand side Dec value for the division.

Returns

An Option<Dec> which is Some with the result if the division is successful, or None if the division cannot be performed.

pub fn zero() -> Dec

The representation of 0

pub fn is_zero(&self) -> bool

Check if value is zero

pub fn one() -> Dec

The representation of 1

pub fn two() -> Dec

The representation of 2

pub fn one_third() -> Dec

The representation of 1 / 3

pub fn two_thirds() -> Dec

The representation of 2 / 3

pub fn two_fifths() -> Dec

The representation of 2 / 5

pub fn new(mantissa: i128, scale: u8) -> Option<Dec>

Create a new Dec using a mantissa and a scale.

pub fn abs_diff(&self, other: Dec) -> Result<Dec, Error>

Get the non-negative difference between two Decs.

pub fn abs(&self) -> Uint

Get the absolute value of self as integer

pub fn to_i256(&self) -> I256

Convert the Dec type into a I256 with truncation

pub fn to_uint(&self) -> Option<Uint>

Convert the Dec type into a Uint with truncation

pub fn checked_sub(&self, rhs: Dec) -> Option<Dec>

Do subtraction of two Decs

pub fn checked_add(&self, other: Dec) -> Option<Dec>

Do addition of two Decs

pub fn checked_mul(&self, other: impl Into<Dec>) -> Option<Dec>

Checked multiplication. Return None if overflow. This methods will overflow incorrectly if both arguments are greater than 128bit.

pub fn checked_div(self, rhs: impl Into<Dec>) -> Option<Dec>

Checked division

pub fn checked_neg(&self) -> Option<Dec>

Checked negation

pub fn is_negative(&self) -> bool

Return if the Dec is negative

pub fn ceil(&self) -> Option<I256>

Return the integer value of a Dec by rounding up.

Trait Implementations

impl BorshDeserialize for Dec

fn deserialize_reader<__R>(reader: &mut __R) -> Result<Dec, Error>

where __R: Read,

fn deserialize(buf: &mut &[u8]) -> Result<Self, Error>

Deserializes this instance from a given slice of bytes. Updates the buffer to point at the remaining bytes.

fn try_from_slice(v: &[u8]) -> Result<Self, Error>

Deserialize this instance from a slice of bytes.

fn try_from_reader<R>(reader: &mut R) -> Result<Self, Error>

where R: Read,

impl BorshSchema for Dec

fn declaration() -> String

Get the name of the type without brackets.

fn add_definitions_recursively(definitions: &mut BTreeMap<String, Definition>)

Recursively, using DFS, add type definitions required for this type. Type definition partially explains how to serialize/deserialize a type.

impl BorshSerialize for Dec

fn serialize<__W>(&self, writer: &mut __W) -> Result<(), Error>

where __W: Write,

impl Clone for Dec

fn clone(&self) -> Dec

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Dec

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

Formats the value using the given formatter.

impl Default for Dec

fn default() -> Dec

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for Dec

fn deserialize<__D>( __deserializer: __D, ) -> Result<Dec, <__D as Deserializer<'de>>::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Display for Dec

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

Formats the value using the given formatter.

impl From<i128> for Dec

fn from(num: i128) -> Dec

Converts to this type from the input type.

impl From<i32> for Dec

fn from(num: i32) -> Dec

Converts to this type from the input type.

impl From<u64> for Dec

fn from(num: u64) -> Dec

Converts to this type from the input type.

impl From<usize> for Dec

fn from(num: usize) -> Dec

Converts to this type from the input type.

impl FromStr for Dec

type Err = Error

The associated error which can be returned from parsing.

fn from_str(s: &str) -> Result<Dec, Error>

Parses a string s to return a value of this type.

impl Hash for Dec

fn hash<__H>(&self, state: &mut __H)

where __H: Hasher,

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Ord for Dec

fn cmp(&self, other: &Dec) -> 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 Dec

fn eq(&self, other: &Dec) -> 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 Dec

fn partial_cmp(&self, other: &Dec) -> 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 Serialize for Dec

fn serialize<__S>( &self, __serializer: __S, ) -> Result<<__S as Serializer>::Ok, <__S as Serializer>::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl TryFrom<Amount> for Dec

type Error = Error

The type returned in the event of a conversion error.

fn try_from(amt: Amount) -> Result<Dec, <Dec as TryFrom<Amount>>::Error>

Performs the conversion.

impl TryFrom<I256> for Dec

type Error = Error

The type returned in the event of a conversion error.

fn try_from(num: I256) -> Result<Dec, <Dec as TryFrom<I256>>::Error>

Performs the conversion.

impl TryFrom<String> for Dec

type Error = Error

The type returned in the event of a conversion error.

fn try_from(value: String) -> Result<Dec, Error>

Performs the conversion.

impl TryFrom<Uint> for Dec

type Error = Error

The type returned in the event of a conversion error.

fn try_from(value: Uint) -> Result<Dec, <Dec as TryFrom<Uint>>::Error>

Performs the conversion.

impl TryFrom<u128> for Dec

type Error = Error

The type returned in the event of a conversion error.

fn try_from(num: u128) -> Result<Dec, <Dec as TryFrom<u128>>::Error>

Performs the conversion.

impl Copy for Dec

impl Eq for Dec

impl StructuralPartialEq for Dec