From 4aa7741ba9b291d9846d55dc520b6982a6dd1aae Mon Sep 17 00:00:00 2001
From: pevnak <pevnak@gmail.com>
Date: Tue, 17 Oct 2017 17:57:10 +0100
Subject: [PATCH] logit cross entropy

---
 src/layers/stateless.jl | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/layers/stateless.jl b/src/layers/stateless.jl
index 5aa812f2..f557dbc4 100644
--- a/src/layers/stateless.jl
+++ b/src/layers/stateless.jl
@@ -6,3 +6,9 @@ crossentropy(ŷ::AbstractVecOrMat, y::AbstractVecOrMat) =
   -sum(y .* log.(ŷ)) / size(y, 2)
 
 @deprecate logloss(x, y) crossentropy(x, y)
+
+function logitcrossentropy(logŷ, y::AbstractMatrix, w)
+  logŷ = logŷ .-maximum(logŷ,1)
+  ypred = logŷ .- log.( sum( exp.( logŷ),1))
+  -sum(y .* w .* ypred)
+end