5.5的损失函数有误

[fecet]

def focal_loss(gamma=2., alpha=.25):
    
    def focal_loss_fixed(y_true, y_pred):
        pt_1 = tf.where(tf.equal(y_true, 1), y_pred, tf.ones_like(y_pred))
        pt_0 = tf.where(tf.equal(y_true, 0), y_pred, tf.zeros_like(y_pred))
        loss = -tf.sum(alpha * tf.pow(1. - pt_1, gamma) * tf.log(1e-07+pt_1)) \
           -tf.sum((1-alpha) * tf.pow( pt_0, gamma) * tf.log(1. - pt_0 + 1e-07))
        return loss
    return focal_loss_fixed

提示 AttributeError: module 'tensorflow' has no attribute 'sum', 猜测应该更正为:

def focal_loss(gamma=2., alpha=.25):
    
    def focal_loss_fixed(y_true, y_pred):
        pt_1 = tf.where(tf.equal(y_true, 1), y_pred, tf.ones_like(y_pred))
        pt_0 = tf.where(tf.equal(y_true, 0), y_pred, tf.zeros_like(y_pred))
        loss = -tf.reduce_sum(alpha * tf.pow(1. - pt_1, gamma) * tf.math.log(1e-07+pt_1)) \
           -tf.reduce_sum((1-alpha) * tf.pow( pt_0, gamma) * tf.math.log(1. - pt_0 + 1e-07))
        return loss
    return focal_loss_fixed

[lyhue1991]

感谢反馈 @fecet 这一块确实有些问题，后面抽时间修改一下。ღ( ´･ᴗ･` )