1.1.1.0 image.setrestoringbeam

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image.setrestoringbeam - Function

1.1.1 Set the restoringbeam
Description

This function sets the restoring beam. Do not do this unless it is a correct thing to do !

You may supply the beam in one of two ways.

First, you can use the argument beam which you must assign to a record containing fields ’major’, ’minor’ and ’positionangle’. Each of these fields contains a quantity. This record is in the same format as one returned by function restoringbeam. If you leave beam unset, no action with it is taken. If the function argument beam is used, the arguments major, minor, & pa are ignored.

Second, you can use the arguments major, minor and pa. Only the ones that you assign are used. Each argument should be assigned either a quantity or a float (units are implicitly those of the current beam - or if none, arcsec for the axes and degrees for the position angle).

You may also delete the restoring beam by setting delete=T (all other arguments are then ignored).

Arguments


Inputs
major	Major axis FWHM, Quantity or float (e.g., 1arcsec). Default is unset.
	allowed:	any
	Default:	variant 1arcsec
minor	Minor axis FWHM, Quantity or float (e.g., 1arcsec). Default is unset.
	allowed:	any
	Default:	variant 1arcsec
pa	Position angle, Quantity or float (e.g., ’5deg’). Default is unset.
	allowed:	any
	Default:	variant 0deg
beam	The complete restoring beam (output of restoringbeam()). Default is unset.
	allowed:	any
	Default:	record
remove	Delete the restoring beam?
	allowed:	bool
	Default:	false
log	Write new beam values to the logger?
	allowed:	bool
	Default:	true

Returns
bool

Example

"""
#
print "\t----\t setrestoringbeam Ex 1 \t----"
ia.maketestimage(’hcn’,overwrite=true)
rb = ia.restoringbeam()        # returns beam in record
print rb
#{’major’: {’unit’: ’arcsec’, ’value’: 53.500004857778549},
# ’minor’: {’unit’: ’arcsec’, ’value’: 34.199998900294304},
# ’positionangle’: {’unit’: ’deg’, ’value’: 6.0}}
rb[’minor’][’value’] = 12.5
ia.setrestoringbeam(beam=rb)   # new beam specified in record
print ia.restoringbeam()
#{’major’: {’unit’: ’arcsec’, ’value’: 53.500004857778549},
# ’minor’: {’unit’: ’arcsec’, ’value’: 12.5},
# ’positionangle’: {’unit’: ’deg’, ’value’: 6.0}}
ia.setrestoringbeam(major=’36arcsec’)  # beam specified using parameter
print ia.restoringbeam()
#{’major’: {’unit’: ’arcsec’, ’value’: 36.0},
# ’minor’: {’unit’: ’arcsec’, ’value’: 12.5},
# ’positionangle’: {’unit’: ’deg’, ’value’: 6.0}}
ia.setrestoringbeam(remove=true)
print ia.restoringbeam()
#{}
ia.setrestoringbeam(major=’53.5arcsec’,minor=’34.2arcsec’,pa=’6deg’)
print ia.restoringbeam()
#{’major’: {’unit’: ’arcsec’, ’value’: 53.5},
# ’minor’: {’unit’: ’arcsec’, ’value’: 34.200000000000003},
# ’positionangle’: {’unit’: ’deg’, ’value’: 6.0}}
ia.close()
#
"""

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