Plane Wave Expansion: Solving Issues with Bohren and Huffman

AI Thread Summary
The discussion centers on challenges faced while implementing a plane wave expansion in spherical harmonics using MATLAB, based on the work of Bohren and Huffman. The user has encountered issues when defining certain components as zero, leading to nonsensical results due to terms becoming infinite as they are divided by sin(m*phi), which approaches zero. Despite the code being largely complete, the user suspects a deeper issue related to the equations referenced in Bohren and Huffman. They are seeking assistance or examples of similar expansions within a MATLAB framework to resolve these problems. Any guidance from others familiar with this field would be greatly appreciated.
falcao
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I've been working on a plane wave expansion in spherical harmonics.. as demonstrated in Bohren and Huffman (if anyone's familiar with it_)... I have more or less finished my code in Matlab and I'm putting in values to expand and compare with the exact solution...


in short, I'm having trouble when defining some of my components as zero... getting results going crazy all over the place.! now I appreciate this would seem like a problem with the code but looking at the equations in Bohren and Huffman(4.19) (and in my code) there seems to be a different problem!..

one of the terms is divisible by a sin(m*phi) value and of course this value is going to go to zero with my phi and then the term goes to infinity! so my result ends up being nonsensical..>

if anyone is familiar with the field t'would be nice to hear!:redface:
 
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or even if anyone has any examples of such an expansion within a MATLAB framework>?!
 
honestly... any help would be massively appreciated!

please!:cry::confused::cry:
 
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