Struct Decibels 

pub struct Decibels(/* private fields */);

A level, a gain, or a loss in decibels, held to a hundredth of a decibel.

One type carries absolute levels in dBm, antenna gains in dBi, and plain ratios in dB, because a link budget adds and subtracts all three. The name of each value in this module says which one it is. Arithmetic saturates rather than overflowing, and the value prints with two decimals and no unit.

Examples

use pamoja_lora::budget::Decibels;

// A 2.15 dBi dipole behind half a decibel of cable.
let net = Decibels::from_hundredths(215) - Decibels::from_tenths(5);
assert_eq!(net.to_string(), "1.65");
assert_eq!(net.round_db(), 2);

Implementations

impl Decibels

pub const ZERO: Self

Zero decibels: no gain and no loss.

pub const fn from_db(db: i32) -> Self

Creates a value from whole decibels.

Arguments

• db - the value in decibels.

Returns

The value, saturating at the range a hundredth-of-a-decibel i32 holds.

pub const fn from_tenths(tenths: i32) -> Self

Creates a value from tenths of a decibel, the precision most antenna datasheets publish.

Arguments

• tenths - the value in tenths of a decibel, so 21 is 2.1 dB.

Returns

The value, saturating at the range a hundredth-of-a-decibel i32 holds.

pub const fn from_hundredths(hundredths: i32) -> Self

Creates a value from hundredths of a decibel, the precision it is held to.

Arguments

• hundredths - the value in hundredths of a decibel, so 215 is 2.15 dB.

Returns

The value.

pub const fn hundredths(self) -> i32

Returns the value in hundredths of a decibel.

Returns

The exact value this type holds.

pub const fn round_db(self) -> i32

Returns the value rounded to whole decibels, halves away from zero.

Returns

The nearest whole decibel, for a figure read in whole decibels. A transmit power setting under a ceiling wants floor_db instead.

pub const fn floor_db(self) -> i32

Returns the value rounded down to whole decibels.

Returns

The largest whole decibel at or below the value, which is how a transmit power setting stays under a ceiling.

Trait Implementations

impl Add for Decibels

type Output = Decibels

The resulting type after applying the + operator.

fn add(self, rhs: Self) -> Self

Performs the + operation.

impl Clone for Decibels

fn clone(&self) -> Decibels

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for Decibels

impl Debug for Decibels

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

Formats the value using the given formatter.

impl Default for Decibels

fn default() -> Decibels

Returns the “default value” for a type.

impl Display for Decibels

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

Formats the value using the given formatter.

impl Eq for Decibels

impl Hash for Decibels

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

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 Neg for Decibels

type Output = Decibels

The resulting type after applying the - operator.

fn neg(self) -> Self

Performs the unary - operation.

impl Ord for Decibels

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

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

Equality operator ==.

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

Inequality operator !=.

impl PartialOrd for Decibels

fn partial_cmp(&self, other: &Decibels) -> 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 StructuralPartialEq for Decibels

impl Sub for Decibels

type Output = Decibels

The resulting type after applying the - operator.

fn sub(self, rhs: Self) -> Self

Performs the - operation.