Simplify spherical_shell, update versions.md

docs/src/versions.md

@@ -38,6 +38,12 @@ Remove `intensities` function. Instead, use one of
 [`intensities_interpolated`](@ref) or [`intensities_binned`](@ref). These will
 require an [`intensity_formula`](@ref), which defines a calculator (e.g., LSWT).
 
+Sunny now expects all wavevectors in units of inverse Angstrom (1/Å). This
+facilitates orientational averaging. Replace `connected_path` with
+[`connected_path_from_rlu`](@ref), which returns wavevectors in 1/Å. Now
+[`spherical_shell`](@ref) needs one fewer argument, and returns wavevectors in
+1/Å.
+
 Rename `polarize_spin!` to [`set_dipole!`](@ref) for consistency with
 [`set_coherent!`](@ref). The behavior of the former function is unchanged: the
 spin at a given site will still be polarized along the provided direction.

examples/longer_examples/CoRh2O4-tutorial.jl

@@ -88,7 +88,7 @@ function powder_average(sc, rs, density; η=0.1, mode=:perp, kwargs...)
     prog   = Progress(length(rs); dt=10., desc="Powder Averaging: ", color=:blue);
     output = zeros(Float64, length(rs), length(ωs(sc)))
     for (i, r) in enumerate(rs)
-        qs = spherical_shell(sc, r, density)
+        qs = spherical_shell(r, density)
         if length(qs) == 0
             qs = [[0., 0., 0.]] ## If radius is too small, just look at 0 vector
         end

examples/powder_averaging.jl

@@ -49,19 +49,18 @@ add_sample!(sc, sys)
 # lorentzian(ω-ω₀, 0.1)`. 
 
 qpoints = [[0.0, 0.0, 0.0], [0.5, 0.0, 0.0], [0.5, 0.5, 0.0], [0.0, 0.0, 0.0]]
-qs, markers = connected_path_from_rlu(crystal, qpoints, 50)
+qs, xticks = connected_path_from_rlu(crystal, qpoints, 50)
 
 is = intensities_interpolated(sc, qs; interpolation=:round, formula = intensity_formula(sc,:trace))
 is_broad = broaden_energy(sc, is, (ω, ω₀) -> lorentzian(ω-ω₀, 0.1))
 
 ## Plot results
 fig = Figure(; resolution=(1000,400))
-xticklabels = [string(tuple(qs[i]...)) for i in markers]
 plotparams = (;
     aspect=1.4,
     ylabel = "ω (meV)",
     xlabel = "𝐪 (RLU)",
-    xticks=(markers, xticklabels),
+    xticks,
     xticklabelrotation=π/10,
     xticklabelsize=14,
 )
@@ -86,7 +85,7 @@ function powder_average(sc, rs, density; η=0.1, kwargs...)
     output = zeros(Float64, length(rs), nω)
 
     for (i, r) in enumerate(rs)
-        qs = spherical_shell(sc, r, density)  # Get points on a sphere of radius r
+        qs = spherical_shell(r, density)  # Get points on a sphere of radius r
         if length(qs) == 0                    
             qs = [[0., 0., 0.]]  # If no points (r is too small), just look at 0 vector
         end

src/Intensities/PowderAveraging.jl

@@ -9,26 +9,23 @@ function spherical_points_fibonacci(N)
 end
 
 """
-    spherical_shell(sc::SampledCorrelations, radius, density)
+    spherical_shell(radius, density)
 
-Returns a set of wave vectors lying on a sphere of specified radius, where
-`radius` is given in ``Å^{-1}``. `density` controls how many points to select
-per ``Å^{-2}``. 
+Sample points on a sphere of given `radius`, with given sample `density`.
 
 The points are generated by mapping a Fibonacci lattice onto a sphere. 
 """
-function spherical_shell(sc::SampledCorrelations, radius, density)
+function spherical_shell(radius, density)
     numpoints = round(Int, 4π*radius^2 * density)
-    crystal = orig_crystal(sc) 
-    C = inv(2π*inv(crystal.latvecs)') # Transformation for inverse angstroms to RLU
-    return if numpoints == 0 
-        [Vec3(0,0,0)]  # If radius too small, just return the 0 vector 
+    if numpoints == 0
+        return [Vec3(0,0,0)]  # If radius too small, just return the 0 vector 
     else
-        map(v->C*v, radius * spherical_points_fibonacci(numpoints))
+        return radius * spherical_points_fibonacci(numpoints)
     end
 end
 
 function powder_average_interpolated(sc::SampledCorrelations, q_ias, density; kwargs...)
+    # FIXME
     A = inv(inv(sc.crystal.latvecs)') # Transformation to convert from inverse angstroms to RLUs
     nω = length(ωs(sc))
     output = zeros(Float64, length(q_ias), nω) # generalize this so matches contract