LogSpiral

class gammapy.astro.population.LogSpiral

Bases: object

Logarithmic spiral.

Reference: http://en.wikipedia.org/wiki/Logarithmic_spiral

Methods Summary

radius(theta, spiralarm_index)	Radius for a given angle.
theta(radius, spiralarm_index)	Angle for a given radius.
xy_position([theta, radius, spiralarm_index])	Compute (x, y) position for a given angle or radius.

Methods Documentation

radius(theta, spiralarm_index)

Radius for a given angle.

Parameters

thetaarray_like

Angle (deg)

spiralarm_indexint

Spiral arm index

Returns

radiusarray_like

Radius (kpc)

theta(radius, spiralarm_index)

Angle for a given radius.

Parameters

radiusarray_like

Radius (kpc)

spiralarm_indexint

Spiral arm index

Returns

thetaarray_like

Angle (deg)

xy_position(theta=None, radius=None, spiralarm_index=0)

Compute (x, y) position for a given angle or radius.

Parameters

thetaarray_like

Angle (deg)

radiusarray_like

Radius (kpc)

spiralarm_indexint

Spiral arm index

Returns

x, yarray_like

Position (x, y)