blocks|key|871511|text|>>>+a+=+numpy.array([[1,5,9],[2,7,3],[8,4,6]])
>>>+numpy.kron(a,+[[1,1],[1,1]])
array([[1,+1,+5,+5,+9,+9],
+++++++[1,+1,+5,+5,+9,+9],
+++++++[2,+2,+7,+7,+3,+3],
+++++++[2,+2,+7,+7,+3,+3],
+++++++[8,+8,+4,+4,+6,+6],
+++++++[8,+8,+4,+4,+6,+6]])|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|871512|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>&gt;&gt;&gt; a = numpy.array([[1,5,9],[2,7,3],[8,4,6]])
&gt;&gt;&gt; numpy.kron(a, [[1,1],[1,1]])
array([[1, 1, 5, 5, 9, 9],
 [1, 1, 5, 5, 9, 9],
 [2, 2, 7, 7, 3, 3],
 [2, 2, 7, 7, 3, 3],
 [8, 8, 4, 4, 6, 6],
 [8, 8, 4, 4, 6, 6]])
</code></pre>

blocks|key|1086342|text|@KennyTM的答案非常巧妙，而且确实适用于您的情况，但作为一种替代方案，它可能会为扩展数组提供更多的灵活性，请尝试np.repeat|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1086343|>>>+a+=+np.array([[1,+5,+9],
++++++++++++++[2,+7,+3],
++++++++++++++[8,+4,+6]])

>>>+np.repeat(a,2,+axis=1)
array([[1,+1,+5,+5,+9,+9],
+++++++[2,+2,+7,+7,+3,+3],
+++++++[8,+8,+4,+4,+6,+6]])|code-block|syntax|javascript|1086344|因此，这完成了沿着一个轴的重复，要让它沿着多个轴重复(正如你可能想要的那样)，只需嵌套np.repeat调用：|1086345|>>>+np.repeat(np.repeat(a,2,+axis=0),+2,+axis=1)
array([[1,+1,+5,+5,+9,+9],
+++++++[1,+1,+5,+5,+9,+9],
+++++++[2,+2,+7,+7,+3,+3],
+++++++[2,+2,+7,+7,+3,+3],
+++++++[8,+8,+4,+4,+6,+6],
+++++++[8,+8,+4,+4,+6,+6]])|1086346|您还可以更改任何初始行或列的重复次数。例如，如果除了最后一行之外，您希望每行重复两次：|1086347|>>>+np.repeat(a,+[2,2,1],+axis=0)
array([[1,+5,+9],
+++++++[1,+5,+9],
+++++++[2,+7,+3],
+++++++[2,+7,+3],
+++++++[8,+4,+6]])|1086348|在这里，当第二个参数是一个行时，它为每一行指定一个重复的逐行(本例中是list，因为是axis=0)。|1086349|entityMap|0|LINK|mutability|MUTABLE|url|https://numpy.org/doc/stable/reference/generated/numpy.repeat.html^0|1N|9|1N|9|0|0|0|17|9|0|0|0|0|Z|4|17|6|0^^$0|@$1|2|3|4|5|6|7|12|8|@$9|13|A|14|B|C]]|D|@$9|15|A|16|1|17]]|E|$]]|$1|F|3|G|5|H|7|18|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|19|8|@$9|1A|A|1B|B|C]]|D|@]|E|$]]|$1|M|3|N|5|H|7|1C|8|@]|D|@]|E|$I|J]]|$1|O|3|P|5|6|7|1D|8|@]|D|@]|E|$]]|$1|Q|3|R|5|H|7|1E|8|@]|D|@]|E|$I|J]]|$1|S|3|T|5|6|7|1F|8|@$9|1G|A|1H|B|C]|$9|1I|A|1J|B|C]]|D|@]|E|$]]|$1|U|3|-4|5|6|7|1K|8|@]|D|@]|E|$]]]|V|$W|$5|X|Y|Z|E|$10|11]]]]

@KennyTM's answer is very slick, and really works for your case but as an alternative that might offer a bit more flexibility for expanding arrays try <a href="https://numpy.org/doc/stable/reference/generated/numpy.repeat.html" rel="noreferrer"><code>np.repeat</code></a>:
<pre><code>&gt;&gt;&gt; a = np.array([[1, 5, 9],
 [2, 7, 3],
 [8, 4, 6]])

&gt;&gt;&gt; np.repeat(a,2, axis=1)
array([[1, 1, 5, 5, 9, 9],
 [2, 2, 7, 7, 3, 3],
 [8, 8, 4, 4, 6, 6]])
</code></pre>
So, this accomplishes repeating along one axis, to get it along multiple axes (as you might want), simply nest the <code>np.repeat</code> calls:
<pre><code>&gt;&gt;&gt; np.repeat(np.repeat(a,2, axis=0), 2, axis=1)
array([[1, 1, 5, 5, 9, 9],
 [1, 1, 5, 5, 9, 9],
 [2, 2, 7, 7, 3, 3],
 [2, 2, 7, 7, 3, 3],
 [8, 8, 4, 4, 6, 6],
 [8, 8, 4, 4, 6, 6]])
</code></pre>
You can also vary the number of repeats for any initial row or column. For example, if you wanted two repeats of each row aside from the last row:
<pre><code>&gt;&gt;&gt; np.repeat(a, [2,2,1], axis=0)
array([[1, 5, 9],
 [1, 5, 9],
 [2, 7, 3],
 [2, 7, 3],
 [8, 4, 6]])
</code></pre>
Here when the second argument is a <code>list</code> it specifies a row-wise (rows in this case because <code>axis=0</code>) repeats for each row.

blocks|key|871640|text|不幸的是，numpy不允许使用小数步(据我所知)。这里有一个解决方法。它不像Kenny的解决方案那么聪明，但它利用了传统的索引：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|871641|>>>+a+=+numpy.array([[1,5,9],[2,7,3],[8,4,6]])
>>>+step+=+.5
>>>+xstop,+ystop+=+a.shape
>>>+x+=+numpy.arange(0,xstop,step).astype(int)
>>>+y+=+numpy.arange(0,ystop,step).astype(int)
>>>+mg+=+numpy.meshgrid(x,y)
>>>+b+=+a[mg].T
>>>+b
array([[1,+1,+5,+5,+9,+9],
+++++++[1,+1,+5,+5,+9,+9],
+++++++[2,+2,+7,+7,+3,+3],
+++++++[2,+2,+7,+7,+3,+3],
+++++++[8,+8,+4,+4,+6,+6],
+++++++[8,+8,+4,+4,+6,+6]])|code-block|syntax|javascript|871642|(dtlussier的解决方案更好)|871643|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

Unfortunately numpy does not allow fractional steps (as far as I am aware). Here is a workaround. It's not as clever as Kenny's solution, but it makes use of traditional indexing:

<pre><code>&gt;&gt;&gt; a = numpy.array([[1,5,9],[2,7,3],[8,4,6]])
&gt;&gt;&gt; step = .5
&gt;&gt;&gt; xstop, ystop = a.shape
&gt;&gt;&gt; x = numpy.arange(0,xstop,step).astype(int)
&gt;&gt;&gt; y = numpy.arange(0,ystop,step).astype(int)
&gt;&gt;&gt; mg = numpy.meshgrid(x,y)
&gt;&gt;&gt; b = a[mg].T
&gt;&gt;&gt; b
array([[1, 1, 5, 5, 9, 9],
 [1, 1, 5, 5, 9, 9],
 [2, 2, 7, 7, 3, 3],
 [2, 2, 7, 7, 3, 3],
 [8, 8, 4, 4, 6, 6],
 [8, 8, 4, 4, 6, 6]])
</code></pre>

(dtlussier's solution is better)

I am working in Python and I have a <a href="http://en.wikipedia.org/wiki/NumPy" rel="noreferrer">NumPy</a> array like this:

<pre><code>[1,5,9]
[2,7,3]
[8,4,6]
</code></pre>

How do I stretch it to something like the following?

<pre><code>[1,1,5,5,9,9]
[1,1,5,5,9,9]
[2,2,7,7,3,3]
[2,2,7,7,3,3]
[8,8,4,4,6,6]
[8,8,4,4,6,6]
</code></pre>

These are just some example arrays, I will actually be resizing several sizes of arrays, not just these.

I'm new at this, and I just can't seem to wrap my head around what I need to do.

Resizing and stretching a NumPy array

Python

我在Python中工作，我有一个数组，如下所示：[1,5,9][2,7,3][8,4,6]如何将其扩展为如下所示？[1,1,5,5,9,9][1,1,5,5,9,9][2,2,7,7,3,3][2,2,7,7,3,3][8,8,4,4,6,6][8,8,4,4,6,6]这些只是一些示例数组，实际上我将调整数组的大小，而...

问调整和拉伸NumPy阵列的大小
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