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imager.pb - Function

2.3.1 Applies or corrects for a primary beam


Description

Multiply (operation=’apply’) or divide (operation=’correct’) by the primary beam function. The primary beam can be applied to images and/or Componentlists.

If pointingcenter==false then you must specify inimage and the pointing center is taken from its reference direction. Otherwise, pointingcenter must be a Direction measure. It cannot take on the value True.

The applied primary beam function is deterimed as follows. If you used function Imager.setvp to set an external voltage pattern table, then this is where the applied primary beam will come from (regardless of whether you set inimage or not). If you did not run this function, then you must supply argument inimage. The telescope name embedded in its Coordinate System will be used to determine the primary beam function.

Arguments





Inputs

inimage

Input image to apply beam to

allowed:

string

Default:

outimage

Output image after beam is applied

allowed:

string

Default:

incomps

Input Componentlist table name

allowed:

string

Default:

outcomps

Output Componentlist table name

allowed:

string

Default:

operation

Operation

allowed:

string

Default:

correct

apply

pointingcenter

Pointing center for primary beam application: default N.Pole

allowed:

any

Default:

variant

parangle

Parallactic angle for calculation

allowed:

any

Default:

variant 0.0deg

pborvp

Primary Beam or Voltage Pattern

allowed:

string

Default:

vb

pb

async

Run asynchronously in the background

allowed:

bool

Default:

false

Returns
bool

Example

 
 
# make a flat image  
im.make(’flat.image’);  
ia.open(’flat.image’);  
arr=ia.getchunk();  
arr[0:len(arr), 0:len(arr[0])] = 1.0;  
ia.putchunk(arr);  
ia.done()  
arr = false;  
#  
# as we are using "pointingcenter=F", it defaults to the image center  
im.pb(inimage=’flat.image’, outimage=’pb.image’, pointingcenter=F)  
 

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