2.3.1.0 imager.setscales

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imager.setscales - Function

2.3.1 Set the scale sizes for MultiScale Clean

Description

The multiscale clean algorithm cleans an image on a number of different scales, decomposing the image into Gaussians of these scale sizes. This function allows the user to set the number of scales used (using the nscales method), or to directly control the sizes of the scales in pixels (using the uservector method). When using the nscales method, the scales are calculated using the following formula:

θminor10.0(i-Nxscales∕2)∕2.0

(2.3)

where θ_min is the fitted minor axis of the clean beam. The first value is zero.

Arguments


Inputs
scalemethod	Method by which scales are set
	allowed:	string
	Default:	nscales uservector nscales
nscales	Number of scales
	allowed:	int
	Default:	5
uservector	Vector of scale sizes in pixels to use, defaults should be 0,3,10
	allowed:	doubleArray
	Default:	0.0 3.0 10.0

Returns
bool

Example

- im.setscales(scalemethod=’nscales’, nscales=6);

Here we make six scales automatically using the method described
above.
Or we could manually choose the scales in pixel numbers as follows:

- im.setscales(scalemethod=’uservector’, uservector=[0,3,10,30]);

Note: 0 pixel is the delta function, so if one were to select scale 0 only
it would be equivalent to a Hogbom clean.

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