From b89b7f0a8c35ca8d3ff63aad844ae47307ffb0da Mon Sep 17 00:00:00 2001
From: William Falcon <falc@fb.com>
Date: Tue, 13 Aug 2019 13:02:17 -0400
Subject: [PATCH] updated docs

---
 docs/LightningModule/RequiredTrainerInterface.md | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/docs/LightningModule/RequiredTrainerInterface.md b/docs/LightningModule/RequiredTrainerInterface.md
index 6569552406..f1f862e802 100644
--- a/docs/LightningModule/RequiredTrainerInterface.md
+++ b/docs/LightningModule/RequiredTrainerInterface.md
@@ -136,7 +136,17 @@ def training_step(self, data_batch, batch_nb):
     
     # return a dict
     return output
-```
+```    
+
+If you define multiple optimizers, this step will also be called with an additional ```optimizer_idx``` param.    
+``` {.python}
+# Multiple optimizers (ie: GANs)     
+def training_step(self, data_batch, batch_nb, optimizer_idx):
+    if optimizer_idx == 0:
+        # do training_step with encoder
+    if optimizer_idx == 1:
+        # do training_step with decoder    
+```    
 
 --- 
 ### tng_dataloader