Struct MagneticField 

#[non_exhaustive]
pub struct MagneticField {

    pub north_nt: f64,
    pub east_nt: f64,
    pub down_nt: f64,
    pub horizontal_nt: f64,
    pub total_nt: f64,
    pub inclination_rad: f64,
    pub declination_rad: f64,
    pub grid_variation_rad: Option<f64>,
    pub north_rate_nt_per_year: f64,
    pub east_rate_nt_per_year: f64,
    pub down_rate_nt_per_year: f64,
    pub horizontal_rate_nt_per_year: f64,
    pub total_rate_nt_per_year: f64,
    pub inclination_rate_rad_per_year: f64,
    pub declination_rate_rad_per_year: f64,
}

The magnetic elements at one place and time, and their rates of change.

Components are in the local geodetic north-east-down frame of the WGS 84 ellipsoid, as the report gives them (hpr’s launch frame is east-north-up: see MagneticField::enu_nt); angles are in radians; rates are per year.

Fields (Non-exhaustive)

Non-exhaustive structs could have additional fields added in future. Therefore, non-exhaustive structs cannot be constructed in external crates using the traditional Struct { .. } syntax; cannot be matched against without a wildcard ..; and struct update syntax will not work.

north_nt: f64

X, the northward component, nT.

east_nt: f64

Y, the eastward component, nT.

down_nt: f64

Z, the downward component, nT.

horizontal_nt: f64

H = √(X² + Y²), the horizontal intensity, nT.

total_nt: f64

F = √(H² + Z²), the total intensity, nT.

inclination_rad: f64

I = atan2(Z, H), the inclination or dip, rad, positive down.

declination_rad: f64

D = atan2(Y, X), the declination, rad, positive east of true north.

grid_variation_rad: Option<f64>

The grid variation poleward of 55° (report, equation 1): D − λ north of 55° N, D + λ south of 55° S, in (−π, π]; None elsewhere.

north_rate_nt_per_year: f64

Ẋ, nT per year.

east_rate_nt_per_year: f64

Ẏ, nT per year.

down_rate_nt_per_year: f64

Ż, nT per year.

horizontal_rate_nt_per_year: f64

Ḣ = (X Ẋ + Y Ẏ) / H, nT per year.

total_rate_nt_per_year: f64

Ḟ = (X Ẋ + Y Ẏ + Z Ż) / F, nT per year.

inclination_rate_rad_per_year: f64

İ = (H Ż − Z Ḣ) / F², rad per year.

declination_rate_rad_per_year: f64

Ḋ = (X Ẏ − Y Ẋ) / H², rad per year. The grid variation changes at the same rate.

Implementations

impl MagneticField

pub fn enu_nt(&self) -> DVec3

The field as east, north and up components, nT: (Y, X, −Z), the axes of hpr’s launch frame (docs/physics/frames.md).

pub fn compass_zone(&self) -> CompassZone

The compass zone at this place, from the horizontal intensity (report, section 1.8). A horizontal intensity that is not a number counts as the blackout zone.

pub fn declination_uncertainty_rad(&self) -> f64

The model’s own estimate of its declination error, one standard deviation, rad (report, section 3.4, equation 43):

δD = √(0.26² + (5417 / H)²)   degrees, with H in nT

About 0.29° where the field is strongest and growing without bound toward a magnetic pole. It covers the coefficients’ and the forecast’s errors, the crust’s local fields the model leaves out, and magnetic storms; a steel rail or car beside a compass adds its own. The report fits it on the ellipsoid’s surface; at height it uses that height’s H, which is weaker, so the estimate grows a little (negligibly at a rocket’s heights).

pub fn true_from_magnetic_rad(&self, magnetic_bearing_rad: f64) -> f64

A true bearing from a magnetic one: true = magnetic + D, rad, in [0, 2π).

Trait Implementations

impl Clone for MagneticField

fn clone(&self) -> MagneticField

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for MagneticField

impl Debug for MagneticField

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for MagneticField

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl PartialEq for MagneticField

fn eq(&self, other: &MagneticField) -> 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 Serialize for MagneticField

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

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for MagneticField