1.2.1.0 componentlist.setshape

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componentlist.setshape - Function

1.2.1 Change the shape of the component

Description

The setshape function changes the shape of the specified components to the user specified shape.

The type argument defines what the sort of new shape to use. This can be either ’point’, ’Gaussian’, ’disk’, or ’limbdarkeneddisk’. The parsing of this string is case insensitive. The ’limbdarkeneddisk’ is an experimental disk model with the limb-darkening effect, where the sky brigtness is described as I=I_o (1-(r/R)**2)**(n/2) with R being apparent body radius. The n can be set in optionalparms (if it is not set, the default value, 0.0 will be used).

If the shape type is ’point’ then the remaining arguments in this function are ignored. There are no other parameters needed to specify a point shape.

But if the shape is ’Gaussian’, ’disk’, or ’limbdarkeneddisk’, the remaining arguments are needed to fully specify the shape. The majoraxis, minoraxis and positionangle arguments are quantities (see the quanta module for a definition of a quantity). Hence they can be specified either as with string eg., ’1arcsec’ or with a record eg., [value=1, unit=’deg’].

The major axis is the width of the larger axis. For the Gaussian shape this is the full width at half maximum. And the minor axis is the width of the orthogonal axis. The positionangle is the specifies the rotation of these two axes with respect to a line connecting the poles of the current direction reference frame. If the angle is positive the the north point of the component moves in the eastern direction.

Arguments


Inputs
which	A vector of indices specifying the components to modify. A vector with indices between 0 and one less than the list length, inclusively
	allowed:	int
	Default:
type	The new shape type. A string that is either ’point’, ’Gaussian’, ’disk’, or ’limbdarkeneddisk’
	allowed:	string
	Default:	disk limbdarkeneddisk Gaussian Point
majoraxis	The width of the larger axis. A quantity with angular units
	allowed:	any
	Default:	1.0arcmin
minoraxis	The width of the smaller axis. A quantity with angular units
	allowed:	any
	Default:	1.0arcmin
positionangle	The rotation of the axes with respect to the reference frame. A quantity with angular units
	allowed:	any
	Default:	0.0deg
majoraxiserror	Error of width of the larger axis. A quantity with angular units
	allowed:	any
	Default:	0.0arcmin
minoraxiserror	Error of the width of the smaller axis. A quantity with angular units
	allowed:	any
	Default:	0.0arcmin
positionangleerror	Error of the rotation of the axes with respect to the reference frame. A quantity with angular units
	allowed:	any
	Default:	0.0deg
optionalparms	optional parameters in a vector (for limbdarkeneddisk)
	allowed:	doubleArray
	Default:	0.0
log	Send a message to the logger
	allowed:	bool
	Default:	true

Returns
bool

Example

      cl.open(’crux.cl’, nomodify=False)
      cl.setshape(3, ’disk’,  ’45mas’, ’45mas’)
      print cl.getshape(3)[’majoraxis’]

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