Angle Units

class coord.AngleUnit(value)[source]

A class for defining angular units used by Angle objects.

Initialization:

An AngleUnit takes a single argument for initialization, a float that specifies the size of the desired angular unit in radians. For example:

coord.AngleUnit.__init__()

>>> gradian = AngleUnit(2. * math.pi / 400.)
>>> print(gradian)
coord.AngleUnit(0.015707963267948967)

Built-in units:

There are five built-in AngleUnits which are always available for use:

coord.radians:coord.AngleUnit(1.)
coord.degrees:coord.AngleUnit(pi / 180.)
coord.hours:coord.AngleUnit(pi / 12.)
coord.arcmin:coord.AngleUnit(pi / 180. / 60.)
coord.arcsec:coord.AngleUnit(pi / 180. / 3600.)

Attribute:

An AngleUnit as the following (read-only) attribute:

value:The measure of the unit in radians.
__init__(value)[source]
Parameters:value – The measure of the unit in radians.
value

A read-only attribute giving the measure of the AngleUnit in radians.

static from_name(unit)[source]

Convert a string into the corresponding AngleUnit.

Only the start of the string is checked, so for instance ‘radian’ or ‘radians’ is equivalent to ‘rad’.

Valid options are:

rad:AngleUnit(1.)
deg:AngleUnit(pi / 180.)
hour or hr:AngleUnit(pi / 12.)
arcmin:AngleUnit(pi / 180. / 60.)
arcsec:AngleUnit(pi / 180. / 3600.)
Parameters:unit – The string name of the unit to return
Returns:an AngleUnit