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1D example
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1D
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2D cartesian
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2D polar Google Hankel transforms!
3D cartesian
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f g x
f x g x x x
f g x y
f x y g x x y y x y
f g x y z
f x y z g x x y y
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' d ' d 'dz '
z z x y
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Convolution - an averaging
operation where at each point
a weighted mean of the
original function is calculated.
The (invariant!!!) weighting
function is often called kernel.
Calculation techniques:
Convolutions - many dose calculation problems can be approximated as convolutions
(invariant kernel -> for homogeneous media):