FIFOQueue '_2_batch/fifo_queue' is closed and has insufficient elements (requested 3, current size 0

出现这个错误的原因是局部变量没有初始化,tensorflow中局部变量初始化函数为tf.local_variables_initializer(),全局变量初始化函数为tf.global_variables_initializer(),如下面的代码,

FIFOQueue '_2_batch/fifo_queue' is closed and has insufficient elements (requested 3, current size 0

去掉局部变量初始化的注释后程序就能运行,

FIFOQueue '_2_batch/fifo_queue' is closed and has insufficient elements (requested 3, current size 0