diff --git a/docs/article/advanced/numpy_exercises_for_data_analysis.md b/docs/article/advanced/numpy_exercises_for_data_analysis.md
index 5dcf2bd..0757a5d 100644
--- a/docs/article/advanced/numpy_exercises_for_data_analysis.md
+++ b/docs/article/advanced/numpy_exercises_for_data_analysis.md
@@ -1672,11 +1672,8 @@ arr
 
 # Solution:
 def one_hot_encodings(arr):
-    uniqs = np.unique(arr)
-    out = np.zeros((arr.shape[0], uniqs.shape[0]))
-    for i, k in enumerate(arr):
-        out[i, k-1] = 1
-    return out
+    maxv = np.max(arr)
+    return np.array([[1 if v==i else 0 for i in range(1,maxv+1)]for v in arr])
 
 one_hot_encodings(arr)
 # > array([[ 0.,  1.,  0.],
@@ -2385,4 +2382,4 @@ print(gen_strides(np.arange(15), stride_len=2, window_len=4))
 
 ## 文章出处
 
-由NumPy中文文档翻译，原作者为 machinelearningplus.com，翻译至：[https://www.machinelearningplus.com/python/101-numpy-exercises-python/](https://www.machinelearningplus.com/python/101-numpy-exercises-python/)
\ No newline at end of file
+由NumPy中文文档翻译，原作者为 machinelearningplus.com，翻译至：[https://www.machinelearningplus.com/python/101-numpy-exercises-python/](https://www.machinelearningplus.com/python/101-numpy-exercises-python/)