Further Reading¶

The first group offers friendly introductions. The second group contains standards, scientific work, and implementation references behind NautiPy’s documented choices. Links are provided instead of bundling copied figures or documents.

Friendly introductions¶

Coordinates and Earth¶

Geographic coordinate system introduces latitude, longitude, and reference surfaces.
Decimal degrees compares common degree notations.
Sexagesimal explains the base-60 origin of angular minutes and seconds.
World Geodetic System introduces WGS84.
GeoJSON introduces Point, Feature, and FeatureCollection objects.

Geodesics on an ellipsoid develops shortest paths on an ellipsoidal Earth model.
Azimuth introduces angular direction from north.
Position fixing surveys how observations locate a vessel.
Resection covers directional constraints to known references.
Trilateration covers distance-intersection geometry.

Fitting and uncertainty¶

Least squares introduces residual minimization.
Condition number explains sensitivity to input error.
Covariance matrix explains multidimensional variation.
Confidence region introduces regions such as a confidence ellipse.
Reduced chi-squared statistic provides context for comparing weighted mismatch and degrees of freedom.

Wikipedia is useful orientation, not NautiPy’s behavioral authority. The project specifications and primary sources below settle the package’s exact conventions.

Standards and primary sources¶

Coordinate representation and interchange¶

ISO 6709:2022 — Standard representation of geographic point location by coordinates. The ISO catalogue page identifies the current standard. NautiPy implements a deliberately smaller, unambiguous signed two-dimensional subset; consult the coordinate specification for that boundary.
NMEA 0183. The official NMEA standard page describes the marine-electronics data standard. NautiPy supports coordinate and direction field pairs, not complete sentences or streams.
RFC 7946 — The GeoJSON Format. The RFC Editor copy defines GeoJSON’s WGS84 decimal-degree position and longitude/latitude array order. NautiPy intentionally limits interchange to two-dimensional Points and Point FeatureCollections.

WGS84 and geodesics¶

National Geospatial-Intelligence Agency WGS 84 resources. The official NGA WGS 84 page collects reference-system definitions and supporting material.
Karney, C. F. F. (2013), “Algorithms for geodesics.” DOI 10.1007/s00190-012-0578-z. This paper develops accurate direct and inverse algorithms for geodesics on an ellipsoid.
GeographicLib. The Python geodesic documentation documents the WGS84 implementation used by NautiPy. NautiPy returns its own small result models rather than exposing backend dictionaries.
Bowditch, The American Practical Navigator. The NGA provides the official publication page, a broad primary reference for practical navigation concepts.

Least squares and measurement uncertainty¶

SciPy least_squares. The SciPy 1.14.1 reference documents the bounded nonlinear least-squares optimizer underlying NautiPy’s private fix solver.
NIST measurement uncertainty. NIST’s Uncertainty of Measurement portal links its policy, guidelines, and Technical Note 1297. These materials explain careful uncertainty statements; NautiPy’s exact statistical model remains the one defined in its position-fix specification.

NautiPy behavior specifications¶

These repository documents are the authoritative contracts for what the package accepts, calculates, and rejects:

The Glossary gives shorter definitions, while the learning path develops the concepts through original visuals and examples.