direction_cosine class

direction_cosine

The direction_cosine class is a descendant of the vector3 class, with the vector length normalized to unity. The dcos is an alias to the direction_cosine.

using dcos = direction_cosine;

Constructors

direction_cosine(const double l, const double m, const double n)

Create a direction_cosine instance with a (l,m,n) coordinate.

l

the l-element of the direction cosine.

m

the m-element of the direction cosine.

n

the n-element of the direction cosine.

direction_cosine(const vector3& p)

Create a direction_cosine instance from another instance.

p

another direction_cosine instance.

direction_cosine(const longitude& lon, const latitude& lat)

Create a direction_cosine instance from a longitude and latitude pair.

lon

a longitude instance.

lat

a latitude instance.

Functions

const double
inner_product(const vector3& v) const

Calculate an inner product with another vector3 instance v. Inherited from the vector3 class.

v

a vector3 instance.

const vector3
outer_product(const vector3& v) const

Calculate an outer product with another vectore instance v. Inherited from the vector3 class.

v

a vector3 instance.

const double
separation_cosine(const vector3& v) const

Calculate cosθ, where θ is the separation angle between another vector3 instance v. Inherited from the vector3 class.

v

a vector3 instance.

const angle
separation(const vector3& v) const

Calculate θ, where θ is the separation angle between another vector3 instance v. Inherited from the vector3 class.

v

a vector3 instance.

const direction_cosine
get_pole(const vector3& v) const

Calculate the pole direction perpendicular to both this instance and a vector3 instance.

v

a vector3 instance.

const direction_cosine
pivot(const direction_cosine& q, const angle& f1, const angle& f2) const

Obtain the direction which is separated by f1 from this instance and separated by f2 from another direction_cosine q.

q

an anchor point.

f1

the separation angle from this instance.

f2

the separation angle from the anchor point q.

const direction_cosine
extend_to(const direction_cosine& q, const angle& d) const

Obtain an extended direction_cosine point toward q. The separation angle from this instance is specified by d.

q

a direction_cosine instance, which defines the direction to extend.

d

a separation angle between this instance and the extended point.

const direction_cosine
extend_to(const direction_cosine& q, const double f) const

Obtain an extended direction_cosine point toward q. The separation from this instance is specified by f, a separation normalized by the distance between this instance and q.

q

a direction_cosine instance, which defines the direction to extend.

f

a separation factor.

void
print() const

Write down the (l,m,n) coordinate in stdout.

Attributes

l

(double) l-element of the direction cosine.

m

(double) m-element of the direction cosine.

n

(double) n-element of the direction cosine.

lon

(longitude) the longitude angle of the direction cosine.

lat

(latitude) the latitude angle of the direction cosine.

x

(double) the reference to the l-element of the direction cosine. Inherited from vector3.

y

(double) the reference to the m-element of the direction cosine. Inherited from vector3.

z

(double) the reference to the n-element of the direction cosine. Inherited from vector3.

d

(double) always unity. Inherited from vector3.