Using DDA on objects with more than one domain

[anna-wang]

Using the example from the tutorial (http://manoharan.seas.harvard.edu/holopy/users/dda_tutorial.html#dda-tutorial) fails:

import holopy as hp
from holopy.core import Optics, ImageSchema
from holopy.scattering.scatterer import Scatterer, Sphere
from holopy.scattering.theory import DDA
s1 = Sphere(r = .5, center = (0, -.4, 0))
s2 = Sphere(r = .5, center = (0, .4, 0))
schema = ImageSchema(100, .1, Optics(.66, 1.33, (1, 0)))
dumbbell = Scatterer(lambda point: s1.contains(point) or s2.contains(point),
1.59, (5, 5, 5))
holo = DDA.calc_holo(dumbbell, schema)

gives error:
ValueError: The truth value of an array with more than one element is ambiguous. Use a.any() or a.all()

[tdimiduk]

That is actually corrected in the most recent version of the docs, if you build it yourself, or look at:
http://people.seas.harvard.edu/~tdimiduk/holopy/

If you want to do a dumbbell like that specifically, you might also try out the CSG Union I added but have not formally documented yet.

from holopy.core import Optics, ImageSchema
from holopy.scattering.scatterer import Union, Sphere
from holopy.scattering.theory import DDA
s1 = Sphere(n=1.59, r = .5, center = (5, 4.6, 5))
s2 = Sphere(n=1.59, r = .5, center = (5, 5.4, 5))
schema = ImageSchema(100, .1, Optics(.66, 1.33, (1, 0)))
dumbbell = Union(s1, s2)
holo = DDA.calc_holo(dumbbell, schema)
# csg scattters do support rotations
holo_rotatated = DDA.calc_holo(dumbbell.rotated(1, 0, 0), schema)

I want to get a little bit of feedback on the interface, but if you think this is sensible after using it, I can move to formally documenting the csg interface.

[anna-wang]

I see. The way it's done now is incompatible with the 10+ other types of
scatterers I've created, such as cylinders with spherical caps, Janus
crescents, floating lenses...

On 29 July 2014 14:24, Tom Dimiduk notifications@github.com wrote:

That is actually corrected in the most recent version of the docs, if you
build it yourself, or look at:
http://people.seas.harvard.edu/~tdimiduk/holopy/

If you want to do a dumbbell like that specifically, you might also try
out the CSG Union I added but have not formally documented yet.

from holopy.core import Optics, ImageSchemafrom holopy.scattering.scatterer import Union, Spherefrom holopy.scattering.theory import DDAs1 = Sphere(n=1.59, r = .5, center = (5, 4.6, 5))s2 = Sphere(n=1.59, r = .5, center = (5, 5.4, 5))schema = ImageSchema(100, .1, Optics(.66, 1.33, (1, 0)))dumbbell = Union(s1, s2)holo = DDA.calc_holo(dumbbell, schema)# csg scattters do support rotationsholo_rotatated = DDA.calc_holo(dumbbell.rotated(1, 0, 0), schema)

I want to get a little bit of feedback on the interface, but if you think
this is sensible after using it, I can move to formally documenting the csg
interface.

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