enforce types and include guides with 0 counts

src/sequencing.jl

@@ -1,5 +1,5 @@
 function counts_to_freqs(samples::Vector{Int64}...)
-    results = []
+    results = Vector{Float64}[]
     for sample in samples
         counts = StatsBase.counts(sample, 1:N*coverage)
         push!(results, counts ./ sum(counts))
@@ -9,26 +9,26 @@ end
 
 function sequencing(depths::Vector{Int64}, guides::Vector{Barcode}, samples::Vector{Float64}...)
     @assert (length(depths) == length(samples)) "Supply exactly one sequencing depth per sample"
-    sequencing_results = []
+    sequencing_results = DataFrame[]
     colnames = fieldnames(Barcode)
     push!(colnames, [:counts, :barcodeid]...)
     coltypes = map(x -> fieldtype(Barcode, x), fieldnames(Barcode))
     push!(coltypes, [Int64, Int64]...)
-    
+
     for i in 1:length(samples)
         reads = rand(Categorical(samples[i]), depths[i])
-        
+
         raw_counts = StatsBase.counts(reads, 1:N*coverage)
-        
+
         bc_fieldnames = fieldnames(Barcode)
         data = Any[coltype[] for coltype in coltypes]
-        
-        for id in unique(reads) 
+
+        for id in 1:N*coverage
             barcode_info = as_array(guides[id])
             push!(barcode_info, [raw_counts[id], id]...)
-            
+
             for i in 1:length(barcode_info)
-                push!(data[i], barcode_info[i]) 
+                push!(data[i], barcode_info[i])
             end
         end
         push!(sequencing_results, DataFrame(data, colnames))