擅长:python、mysql、java
<p>这能解决你的问题吗</p>
<pre><code>import numpy as np
list = ['A','A','A','A','B','B','B','B']
array = np.array([ [5.1, 3.5, 1.4, 0.2],
[4.9, 3. , 1.4, 0.2],
[4.7, 3.2, 1.3, 0.2],
[4.6, 3.1, 1.5, 0.2],
[5. , 3.6, 1.4, 0.2],
[5.4, 3.9, 1.7, 0.4],
[4.6, 3.4, 1.4, 0.3],
[5. , 3.4, 1.5, 0.2] ])
idxA = np.array([i for i, x in enumerate(list) if x == "A"])
idxB = np.array([i for i, x in enumerate(list) if x == "B"])
print(np.mean(array[idxA]))
print(np.mean(array[idxB]))
</code></pre>
<p>输出:</p>
<pre><code>2.40625
2.5875000000000004
</code></pre>