我实现了tanh函数作为我的激活函数，但结果在某种程度上比使用sigmoid激活函数更糟糕。此外，在检查错误时，它会反复显示错误再次上升和下降。
以下是使用tanh的错误示例：
epoch:1823
current error:0.1383121756710299
epoch:1824
current error:0.13831547638188654
epoch:1825
current error:0.13831887880040633
epoch:1826
current error:0.13832238240031222
epoch:1827
current error:0.13832598673034413
epoch:1828
current error:0.1383296914155071
epoch:1829
current error:0.13833349615821078
epoch:1830
current error:0.13833740073931955
epoch:1831
current error:0.1383414050191362
epoch:1832
current error:0.13834550893832906
epoch:1833
current error:0.1383497125188264
epoch:1834
current error:0.13835401586468998
epoch:1835
current error:0.1383584191629793
epoch:1836
current error:0.13836292268462677
epoch:1837
current error:0.1383675267853283
epoch:1838
current error:0.13837223190646183
epoch:1839
current error:0.13837703857605013
epoch:1840
current error:0.138381947409767
epoch:1841
current error:0.1383869591120036
epoch:1842
current error:0.13839207447699467
epoch:1843
current error:0.13839729439001985
epoch:1844
current error:0.1384026198286766
epoch:1845
current error:0.1384080518642369
同时，sigmoid激活功能并未显示此信息。有没有人知道为什么会这样？