利用TensorFlow搭建神经网络并tensorbord可视化

本示例，主要有两个目的，第一个是学习搭建DNN网络，第二个是学习tensorbord工具。
github:https://github.com/Great1414/TensorFlow_DNN/blob/master/DNN_practice.py

import tensorflow as tf
from sklearn.datasets import load_boston
from sklearn.preprocessing import scale
from sklearn.model_selection import train_test_split
#数据
boston = load_boston()
X_train, X_test, y_train, y_test = train_test_split(
    boston.data, boston.target, test_size=0.15, random_state= 0 )
X_train = scale(X_train)
X_test = scale(X_test)
y_train = scale(y_train.reshape((-1,1)))
y_test = scale(y_test.reshape((-1,1)))
#占位符与dropout
xs = tf.placeholder(tf.float32, shape=[None,X_train.shape[1]], name="inputs")
ys = tf