Changes between Version 3 and Version 4 of Ticket #332, comment 2
- Timestamp:
- Jan 7, 2016 8:13:11 AM (9 years ago)
Legend:
- Unmodified
- Added
- Removed
- Modified
-
Ticket #332, comment 2
v3 v4 5 5 !SasView is using: 6 6 7 <I ^2^(q)> = pi/2 ∫ ∫ I2(q,θ,ϕ)P1(q,θ)P2(q,ϕ)|cos(θ)| dθ dϕ7 <I(q)> = pi/2 ∫ ∫ I(q,θ,ϕ)P,,1,,(q,θ)P,,2,,(q,ϕ)|cos(θ)| dθ dϕ 8 8 9 9 I can't find a reference that includes the cosine term, or the pi/2 … … 11 11 Perhaps the confusion arose from the different forms of the ellipsoid of revolution. Eq 2.32 gives the ellipsoid of revolution as: 12 12 13 i(h) = ∫,,0,,^pi/2^ Phi 2(h a √(cos2 θ + v2 sin2 θ) cos θ dθ13 i(h) = ∫,,0,,^pi/2^ Phi^2^(h a √(cos2 θ + v2 sin2 θ) cos θ dθ 14 14 15 15 but the 1-D ellipsoid kernel employs the substitution u = sin theta so it is evaluated as 16 16 17 i(h) = ∫,,0,,^1^ Phi 2(h a √(1 + u2(v2 - 1)) du17 i(h) = ∫,,0,,^1^ Phi^2^(h a √(1 + u2(v2 - 1)) du 18 18 19 19 [Note: the u variable above is incorrectly named as cos_alpha in the code.]