Setting-up-Keras-and-Tensorflow-for-Neural-net-Based-models.md

+PyOD includes some neural network based models written in **Keras**, such as AutoEncoder. However, you may find that after **pip install pyod**, AutoEncoder models do not run. This is expected because we do not want PyOD relies on too many packages, and not everyone needs to run neural nets.
+
+If you want to run neural-net based models, please first install **Keras** + a backend library, e.g., tensorflow. Either of the following two should do the installation for you:
+
+* `pip install keras tensorflow or pip install keras tensorflow`
+* `conda install keras tensorflow or pip install keras tensorflow`
+
+**If you have tensorflow-gpu installed, keras would automatically run with GPU.** You need tensorflow-gpu if your device have GPU and want to leverage it, otherwise a normal version TensorFlow should be totally fine.
+
+* `pip install keras tensorflow or pip install keras tensorflow-gpu`
+* `conda install keras tensorflow or pip install keras tensorflow-gpu`
+
+
+***
+
+
+Here are some potential error messages you may encounter:
+
+* ModuleNotFoundError: No module named 'theano'
+
+In this case, you should specify keras backend to the one you want to use, e.g., TensorFlow
+Go to $HOME/.keras/keras.json, and change the "backend" to "tensorflow"
+
+* ModuleNotFoundError: No module named 'error'
+
+In this case, you need to install keras and tensorflow with conda, which can either be done in the GUI or simply use "conda install keras" and "conda install tensorflow"