From 956d869ef03ab155337e2f9fa9b970eb639f87db Mon Sep 17 00:00:00 2001
From: wolfgang-n <33723682+wolfgang-n@users.noreply.github.com>
Date: Mon, 9 Sep 2019 17:19:27 +0200
Subject: [PATCH] Make entropy_vn type-stable

---
 src/metrics.jl | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/metrics.jl b/src/metrics.jl
index 57b6023b..36c55dd1 100644
--- a/src/metrics.jl
+++ b/src/metrics.jl
@@ -152,9 +152,9 @@ natural logarithm and ``0\\log(0) ≡ 0``.
 * `tol=1e-15`: Tolerance for rounding errors in the computed eigenvalues.
 """
 function entropy_vn(rho::DenseOperator{B,B}; tol::Float64=1e-15) where B<:Basis
-    evals = eigvals(rho.data)
-    evals[abs.(evals) .< tol] .= 0.0
-    sum([d == 0 ? 0 : -d*log(d) for d=evals])
+    evals::Vector{ComplexF64} = eigvals(rho.data)
+    evals[abs.(evals) .< tol] .= 0.0im
+    sum([d == 0.0im ? 0.0im : -d*log(d) for d=evals])
 end
 entropy_vn(psi::StateVector; kwargs...) = entropy_vn(dm(psi); kwargs...)