HTN20190109 https://blog.hatena.ne.jp/HTN20190109/ HTN20190109の日記 https://htn20190109.hatenablog.com/ DL import numpy as np class Sigmoid: def forward(self, x, w, b): """ x: (N, D) w: (D,) b: scalar """ self.x = x self.w = w z = np.dot(x, w) + b # ← こっちの方が安全 self.y_pred = 1 / (1 + np.exp(-z)) return self.y_pred def backward(self, dy): """ dy: (N,) """ dz = dy * (1.0 - self.y_pred) * self.y_pred # (N,) … 190 <iframe src="https://hatenablog-parts.com/embed?url=https%3A%2F%2Fhtn20190109.hatenablog.com%2Fentry%2F2026%2F03%2F26%2F012213" title="Sigmoid and NLL - HTN20190109の日記" class="embed-card embed-blogcard" scrolling="no" frameborder="0" style="display: block; width: 100%; height: 190px; max-width: 500px; margin: 10px 0px;"></iframe> Hatena Blog https://hatena.blog 2026-03-26 01:22:13 rich https://htn20190109.hatenablog.com/entry/2026/03/26/012213 1.0 100%