add the prep combinations functions, which helps with external calls

src/SpectralUnmixing.jl

@@ -34,6 +34,7 @@ include("Plotting.jl")
 # Endmember Library Functions
 export SpectralLibrary, load_data!, filter_by_class!, read_envi_wavelengths, interpolate_library_to_new_wavelengths!, remove_wavelength_region_inplace!, scale_library!
 export reduce_endmembers_nmf!, reduce_endmembers_kmeans!, reduce_endmembers_pca!, brightness_normalize!, split_library
+export prepare_combinations, prepare_options, scale_data
 
 # Plotting Functions
 export plot_mean_endmembers, plot_endmembers, plot_endmembers_individually
@@ -240,6 +241,36 @@ function unmix_pixel(library::SpectralLibrary, img_dat_input::Array{Float64}, un
 
 end
 
+function prepare_combinations(library::SpectralLibrary, combination_type::String)
+    class_idx = []
+    if combination_type == "class-even"
+        for uc in library.class_valid_keys
+            push!(class_idx, (1:size(library.classes)[1])[library.classes .== uc])
+        end
+    end
+    return class_idx
+end
+
+function prepare_options(library::SpectralLibrary, combination_type::String, num_endmembers::Vector{Int64}, class_idx)
+
+    # Prepare combinations if relevant
+    options = []
+    if combination_type == "class-even"
+        options = collect(Iterators.product(class_idx...))[:]
+    elseif combination_type == "all"
+        for num in num_endmembers
+            combo = [c for c in combinations(1:length(library.classes), num)]
+            push!(options,combo...)
+        end
+    else
+        error("Invalid combiation string")
+    end
+
+    return options
+end
+
+
+
 function unmix_line(line::Int64, reflectance_file::String, mode::String, refl_nodata::Float64,
                     refl_scale::Float64, normalization::String, library::SpectralLibrary,
                     reflectance_uncertainty_file::String = "", n_mc::Int64 = 1,
@@ -268,26 +299,10 @@ function unmix_line(line::Int64, reflectance_file::String, mode::String, refl_no
     scale_data(img_dat, library.wavelengths[library.good_bands], normalization)
     img_dat = img_dat ./ refl_scale
 
-    class_idx = []
-    if combination_type == "class-even"
-        for uc in library.class_valid_keys
-            push!(class_idx, (1:size(library.classes)[1])[library.classes .== uc])
-        end
-    end
-
+    class_idx = prepare_combinations(library, combination_type)
     # Prepare combinations if relevant
-    options = []
     if mode == "mesma" || mode == "mesma-best"
-        if combination_type == "class-even"
-            options = collect(Iterators.product(class_idx...))[:]
-        elseif combination_type == "all"
-            for num in num_endmembers
-                combo = [c for c in combinations(1:length(library.classes), num)]
-                push!(options,combo...)
-            end
-        else
-            error("Invalid combiation string")
-        end
+        options = prepare_options(library, combination_type, num_endmembers, class_idx)
     end
 
     start_time = time()
@@ -369,12 +384,7 @@ function simulate_pixel(library::SpectralLibrary, max_components::Int64, combina
     output_mixture = zeros(size(library.spectra)[2])
     output_mixture[:] .= NaN
 
-    class_idx = []
-    if combination_type == "class-even"
-        for uc in library.class_valid_keys
-            push!(class_idx, (1:size(library.classes)[1])[library.classes .== uc])
-        end
-    end
+    class_idx = prepare_combinations(library, combination_type)
     perm = get_sma_permutation(class_idx, [max_components], combination_type, size(library.spectra)[1])
 
     G = library.spectra[perm,:]