Tesseral Spherical Harmonics
julia
using GLMakie
using AssociatedLegendrePolynomials
GLMakie.activate!()
GLMakie.closeall() # close any open screen
function Y(θ, ϕ, l, m)
if m < 0
return (-1)^m * √2 * Nlm(l, abs(m)) * Plm(l, abs(m), cos(θ)) * sin(abs(m) * ϕ)
elseif m == 0
return sqrt((2 * l + 1) / 4π) * Plm(l, m, cos(θ))
else
return (-1)^m * √2 * Nlm(l, m) * Plm(l, m, cos(θ)) * cos(m * ϕ)
end
end
# Grids of polar and azimuthal angles
θ = LinRange(0, π, 200)
ϕ = LinRange(0, 2π, 200)
x = [sin(θ) * sin(ϕ) for θ in θ, ϕ in ϕ]
y = [sin(θ) * cos(ϕ) for θ in θ, ϕ in ϕ]
z = [cos(θ) for θ in θ, ϕ in ϕ]
l = 10
m = 1
Ygrid = [Y(θ, ϕ, l, m) for θ in θ, ϕ in ϕ]
Ylm = abs.(Ygrid)
cmap = [:dodgerblue, :white, :orangered]
with_theme(theme_dark()) do
fig = Figure(size = (1200, 800), fontsize = 22)
axs = [Axis3(fig[1, j], aspect = :data) for j in 1:2]
pltobj = surface!(axs[1], x, y, z; color = Ygrid,
colormap = cmap,
shading = NoShading)
surface!(axs[2], Ylm .* x, Ylm .* y, Ylm .* z;
color = Ygrid,
colormap = cmap,
shading = NoShading)
Colorbar(fig[1, 3], pltobj, label = "Yₗₘ(θ,ϕ)", tickwidth = 2, tickalign = 1,
width = 25, ticksize = 25, height = Relative(0.5))
fig[0, 1:2] = Label(fig, "Tesseral Spherical Harmonics l = $(l), m = $(m)",
fontsize = 30, color = (:white, 0.85))
hidedecorations!.(axs; grid = false)
fig
end