#
# Load the setup script, defining TopRowMask, etc..
#
>>> from param import resolve_path
>>> execfile(resolve_path('tests/sheetmask_setup.py'))
>>> from topo.base.boundingregion import BoundingBox
>>> ProjectionSheet.nominal_bounds=BoundingBox(radius=0.5)
>>> s = ProjectionSheet(nominal_density=2,mask=LeftColMask() & TopRowMask())
>>> s.mask.data
array([[1, 0],
       [0, 0]])
>>> s = ProjectionSheet(nominal_density=2,mask=LeftColMask() | TopRowMask())
>>> s.mask.data
array([[1, 1],
       [1, 0]])
>>> s = ProjectionSheet(nominal_density=2,mask=LeftColMask() | TopRowMask() | RightColMask())
>>> s.mask.data
array([[1, 1],
       [1, 1]])
>>> s = ProjectionSheet(nominal_density=2,mask=LeftColMask() & TopRowMask() | RightColMask())
>>> s.mask.data
array([[1, 1],
       [0, 1]])
>>> s = ProjectionSheet(nominal_density=2,mask=LeftColMask() & (TopRowMask() | RightColMask()))
>>> s.mask.data
array([[1, 0],
       [0, 0]])
>>> 
