鍦≒ython涓紝backward()鍑芥暟鏄敤浜庤绠楁搴︾殑鍑芥暟锛屽畠閫氬父涓庤嚜鍔ㄥ井鍒嗘満鍒朵竴璧蜂娇鐢ㄣ€備笅闈㈡槸backward()鍑芥暟鐨勪娇鐢ㄦ柟娉曪細

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涓嬮潰鏄竴涓畝鍗曠殑绀轰緥锛屽睍绀轰簡濡備綍浣跨敤backward()鍑芥暟璁＄畻寮犻噺鐨勬搴︼細

import torch

# 鍒涘缓涓€涓紶閲忓苟璁剧疆requires_grad=True
x = torch.tensor(2.0, requires_grad=True)

# 瀹氫箟涓€涓嚱鏁?y = x^2
y = x**2

# 瀹氫箟涓€涓崯澶卞嚱鏁?/span>
loss = y - 4

# 璋冪敤backward鍑芥暟璁＄畻姊害
loss.backward()

# 鎵撳嵃姊害
print(x.grad)  # 杈撳嚭 4.0

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闇€瑕佹敞鎰忕殑鏄紝鍦ㄥ疄闄呭簲鐢ㄤ腑锛岄€氬父浼氬湪妯″瀷璁粌鐨勬瘡涓€娆¤凯浠ｄ腑浣跨敤backward()鍑芥暟鏉ヨ绠楁搴︼紝骞剁粨鍚堜紭鍖栫畻娉曪紙濡傛搴︿笅闄嶏級鏉ユ洿鏂版ā鍨嬬殑鍙傛暟銆?/p>