# distance

Distance between points on sphere or ellipsoid

## Syntax

## Description

`[`

calculates the arc length `arclen`

,`az`

] = distance(`lat1`

,`lon1`

,`lat2`

,`lon2`

)`arclen`

and azimuth
`az`

of the great circle arc from the starting point with
coordinates `lat1`

and `lon1`

to the
ending point with coordinates `lat2`

and
`lon2`

. The function uses the shorter (minor) great
circle arc. This syntax references the coordinates to a sphere and returns
`arclen`

and `az`

as spherical
distances in degrees.

## Examples

## Input Arguments

## Output Arguments

## Tips

You can convert spherical distances to linear distances by using conversion functions
such as `deg2km`

and `deg2nm`

.

## Algorithms

The accuracy of geodesic azimuth calculations decreases as the distance between the points increases. Additionally, the calculations can break down when the points are nearly antipodal or close to the equator.

When you specify a reference ellipsoid and two points that are both close to the
equator and nearly antipodal, the `distance`

function issues a
warning and returns both `arclen`

and `az`

as values
of `NaN`

.

## Version History

**Introduced before R2006a**