一个通过检测布林带收敛时上下轨差值的ea，在布林带发散过程中选择方向进行交易。-A detected by Bollinger Bands convergence when the upper and lower rail difference in EA, Bollinger Bands the divergence process to choose the direction of trade.

布林轨，做外汇必用的指标，这个带买卖信号的，方便。(Brin Rail, as a necessary indicator of foreign exchange, this with trading signals, convenient.)