1.1.2.0 regionmanager.wmask

NRAO Home > CASA > CasaRef

regionmanager.wmask - Function

1.1.2 Create a world mask region
Description

NOT IMPLEMENTED IN CASA

This function creates a mask region. This region can be applied on-the-fly to images. The expression must be Boolean.

Arguments


Inputs
expr	Boolean expression
	allowed:	string
	Default:	String

Returns
anyrecord

Example

- ia.imagemaketestimage(’zz’)
- r = rg.wmask(expr=’zz>0’)
- ia.statistics(region=r.torecord())

The mask region effectively creates a (notional) Boolean lattice. In this example, when the pixel values are greater than zero, the lattice is True (good), else False. The statistics, when evaluated, are then only computed when the mask region is True.

Example

- ia.imagemaketestimage(’zz’)
- rg.setcoordinates(ia.coordsys().torecord() )
#
- r1 = rg.wbox(...)                 # Make a world box
- r2 = rg.wmask(expr=’zz>0’)        # Make a mask region
- r3 = rg.intersection (r1,r2)      # Intersect them
- ia.statistics(region=r3)            # Find statistics

In this example, the mask is only applied when the pixels fall in the specified box.

[next] [prev] [prev-tail] [front] [up]

Please send any comments or questions about CASA or AIPS++ to aips2-requests@nrao.edu

This code is available under the terms of the GNU General Public Lincense