擅长:python、mysql、java
<blockquote>
<ol>
<li>How can I now create a matrix from the output again.</li>
</ol>
</blockquote>
<p>您可以以矢量化的方式执行该操作,只需为<code>np.compress</code>指定<code>axis</code>关键字</p>
<pre><code>np.compress(u, square_matrix, axis=1)
</code></pre>
<p>输出:</p>
<pre><code>array([[ 1, 3],
[ 5, 7],
[ 9, 11],
[13, 15]])
</code></pre>
<blockquote>
<ol start="2">
<li>How could I repeat the same process for the columns. (My initial idea was to use a transpose of u)</li>
</ol>
</blockquote>
<p>您的建议是正确的,但是将矩阵替换为<code>u</code>。这将用行切换列</p>
<pre><code>np.compress(u, square_matrix.T, axis=1)
</code></pre>
<p>输出:</p>
<pre><code>array([[ 1, 9],
[ 2, 10],
[ 3, 11],
[ 4, 12]])
</code></pre>