1、安装python3、tensorflow、numpy、scipy

安装python3及开发工具

sudo apt-get install python3
sudo apt-get install python-setuptools

安装pip

sudo apt-get install python3-pip

安装tensorflow/numpy/scipy

pip3 install numpy
pip3 install scipy
pip3 install tensorflow

2、安装keras

pip3 install keras

3、安装成功之后的效果

ubuntu:~$ python3
Python 3.5.3 (default, Jan 19 2017, 14:11:04) 
[GCC 6.3.0 20170118] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import keras
Using TensorFlow backend.
>>> exit()

修改keras配置文件，可以更改keras后端依赖的框架：
vim ~/.keras/keras.json

{"image_data_format": "channels_last","epsilon": 1e-07,"backend": "tensorflow","floatx": "float32"
}

把tensorflow改为theano，
同时把channels_last改为channels_first,
即可切换后端框架，如下：

{"image_data_format": "channels_first","epsilon": 1e-07,"backend": "theano","floatx": "float32"
}