Improve performance of unweighted ecdf

Author: devmotion

Project.toml

@@ -1,7 +1,7 @@
 name = "StatsBase"
 uuid = "2913bbd2-ae8a-5f71-8c99-4fb6c76f3a91"
 authors = ["JuliaStats"]
-version = "0.34.6"
+version = "0.34.7"
 
 [deps]
 AliasTables = "66dad0bd-aa9a-41b7-9441-69ab47430ed8"

src/empirical.jl

@@ -55,10 +55,14 @@ function is inside the interval ``(0,1)``; the function is defined for the whole
 """
 function ecdf(X::AbstractVector{<:Real}; weights::AbstractVector{<:Real}=Weights(Float64[]))
     any(isnan, X) && throw(ArgumentError("ecdf can not include NaN values"))
-    isempty(weights) || length(X) == length(weights) || throw(ArgumentError("data and weight vectors must be the same size," *
-        "got $(length(X)) and $(length(weights))"))
-    ord = sortperm(X)
-    ECDF(X[ord], isempty(weights) ? weights : Weights(weights[ord]))
+    if isempty(weights)
+        return ECDF(sort(X), weights)
+    else
+        length(X) == length(weights) || throw(ArgumentError("data and weight vectors must be the same size," *
+            "got $(length(X)) and $(length(weights))"))
+        ord = sortperm(X)
+        ECDF(X[ord], weights[ord])
+    end
 end
 
 minimum(ecdf::ECDF) = first(ecdf.sorted_values)