2.3.1.0 imager.regiontoimagemask

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imager.regiontoimagemask - Function

2.3.1 union a mask image with various regions

Description

This function is very similar to regionmask function except that the mask image has to be existant already and this is an independent helper function (i.e does not care about the state of the imager tool... e.g does not need imager to have an attached ms).

Arguments


Inputs
mask	name of mask image
	allowed:	string
	Default:
region	Region record usually from regionmanager
	allowed:	record
	Default:	unset
boxes	list of 4 elements lists e.g [[xblc1, yblc1, xtrc1, ytrc1], [[xblc2, yblc2, xtrc2, ytrc2]]
	allowed:	any
	Default:	variant
circles	list of 3 elements lists e.g [[rad0, xcen0, ycen0], [rad1,xcen1, ycen1], .....]
	allowed:	any
	Default:	variant
value	Value to set the mask to
	allowed:	double
	Default:	1.0

Returns
bool

Example

Makes a mask then cleans using it.

a=[100.0, 100.0, 200, 200.0]
b=[50, 50, 80, 80]
im.regiontoimagemask(mask=’bigmask’, boxes=[a,b])
im.clean(mask=’bigmask’, model=’3C273XC1.clean.masked’, niter=1000)

Another example using rg.wbox function:
ia.open(’dirty’)
cs = ia.coordsys()
rg.setcoordinates(cs.record())
r1 = dg.wbox(blc=[’173pix’, ’347pix’], trc=[’183pix’, ’370pix’])
im.regionmask(mask=’bigmask’,region=r1)

Or using a dict of regions:

r2=rg.wbox(blc=[’180pix’, ’344pix’], trc=[’191pix’, ’369pix’])
r3=rg.wbox(blc=[’189pix’, ’341pix’], trc=[’204pix’, ’364pix’])
regs={"reg1"’:r1, "reg2":r2, "reg3":r3}
rec=rg.makeunion(regs)
im.regionmask(mask=’bigmask’,region=rec)

If quantities are to be used to define regions the following is a an example

im.regionmask(mask=’joetest’,boxes=[’15:23:32.902’,’+05.19.32.089’,’15:22:28.631’,’+05.28.52.474’])

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