tensorboard可视化遇到的问题

由于 TensorFlow版本差异，经常会报模块对象没有某属性的错误，先把tensorboard可视化过程遇到的几个报错解决方案记录如下：

1. AttributeError: 'module' object has no attribute 'histogram_summary'

histogram_summary 改为：tf.summary.histogram

2. AttributeError: 'module' object has no attribute 'scalar_summary'

tf.scalar_summary 改为：tf.summary.scalar

3.AttributeError: 'module' object has no attribute 'merge_all_summaries'

tf.merge_all_summaries() 改为：tf.summary.merge_all()