blocks|key|1008542|text|我不确定我是否理解，但是如果你想修改x的位置，你会想做一些不同的事情。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1008543|下面的代码应该可以做你需要的事情。|1008544|x+=+zeros(Float64,+2,+2,+2)

function+init!(p,+y,+k)+
++++y[:,+:,+k]+=+ones(Float64,+p,+p)+
end


for+k+=+1:2
+++init!(2,+x,+k)
end|code-block|syntax|javascript|1008545|您可能还想记住，Julia中的标准约定是在修改其参数的函数的名称中包含一个感叹号。如果我理解了您的问题，那么您希望您的init!()函数能够做到这一点。|offset|length|style|CODE|1008546|entityMap^0|0|0|0|1N|7|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|R|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|S|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|T|8|@$K|U|L|V|M|N]]|9|@]|A|$]]|$1|O|3|-4|5|6|7|W|8|@]|9|@]|A|$]]]|P|$]]

I'm not certain I understand, but if you're trying to modify x in place, you'll want to do things a little differently. 

The code below should do what you need.

<pre class="lang-julia prettyprint-override"><code>x = zeros(Float64, 2, 2, 2)

function init!(p, y, k) 
 y[:, :, k] = ones(Float64, p, p) 
end


for k = 1:2
 init!(2, x, k)
end
</code></pre>

And you might also want to keep in mind that the standard convention in Julia is to include an exclamation mark in the name of a function that modifies its arguments. And if I've understood your question, then you want your <code>init!()</code> function to do exactly that.

blocks|key|4597373|text|我也不确定我是否理解了这个问题，但slice(x,+:,+:,+k)将从x中分到2d部分。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|4597374|如果您将x初始化为Float64的数组，然后希望为每个元素分配一个矩阵(这似乎是您正在尝试做的)，那么这是行不通的-+x的类型不允许这样做。您可以使x成为一个Any数组，然后这将是允许的。|4597375|entityMap^0|H|H|10|1|0|4|1|9|7|1N|1|22|1|27|3|0^^$0|@$1|2|3|4|5|6|7|J|8|@$9|K|A|L|B|C]|$9|M|A|N|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|O|8|@$9|P|A|Q|B|C]|$9|R|A|S|B|C]|$9|T|A|U|B|C]|$9|V|A|W|B|C]|$9|X|A|Y|B|C]]|D|@]|E|$]]|$1|H|3|-4|5|6|7|Z|8|@]|D|@]|E|$]]]|I|$]]

I'm also not sure I understand the question, but <code>slice(x, :, :, k)</code> will take a 2d slice of <code>x</code>.

If you're initializing <code>x</code> as an array of <code>Float64</code> and then hoping to assign a matrix to each element (which is what it appears you're trying to do), that won't work---the type of <code>x</code> won't allow it. You could make <code>x</code> an array of <code>Any</code>, and then that would be permitted.

blocks|key|1008566|text|一种可能的解决方案是使用slice，它制作了一个SubArray|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1008567|x+=+zeros(2,+2,+2)++#+Float64+by+default

function+init!(y)
++++y[:]+=+ones(y)++#+change+contents+not+binding
end

for+k+in+1:2
++++init!(slice(x,+:,+:,+k))++#+use+slice+to+get+SubArray+
end|code-block|syntax|javascript|1008568|请注意，您可以使用ones(y)来获取与y大小相同的向量。|1008569|SubArray提供了数组的视图，而不是副本。在未来的Julia版本中，默认情况下，索引数组可能会提供此功能，但目前您必须显式执行此操作。|1008570|有关值与绑定的讨论，请参见|1008571|http://www.johnmyleswhite.com/notebook/2014/09/06/values-vs-bindings-the-map-is-not-the-territory/|1008572|编辑:我没有看到@tholy的答案，它包含了同样的想法。|1008573|entityMap|0|LINK|mutability|MUTABLE|url^0|C|5|O|8|0|0|9|7|K|1|0|0|8|0|0|0|2Q|0|0|0^^$0|@$1|2|3|4|5|6|7|11|8|@$9|12|A|13|B|C]|$9|14|A|15|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|16|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|17|8|@$9|18|A|19|B|C]|$9|1A|A|1B|B|C]]|D|@]|E|$]]|$1|M|3|N|5|6|7|1C|8|@$9|1D|A|1E|B|C]]|D|@]|E|$]]|$1|O|3|P|5|6|7|1F|8|@]|D|@]|E|$]]|$1|Q|3|R|5|6|7|1G|8|@]|D|@$9|1H|A|1I|1|1J]]|E|$]]|$1|S|3|T|5|6|7|1K|8|@]|D|@]|E|$]]|$1|U|3|-4|5|6|7|1L|8|@]|D|@]|E|$]]]|V|$W|$5|X|Y|Z|E|$10|R]]]]

One possible solution is to use <code>slice</code>, which makes a <code>SubArray</code>:

<pre class="lang-julia prettyprint-override"><code>x = zeros(2, 2, 2) # Float64 by default

function init!(y)
 y[:] = ones(y) # change contents not binding
end

for k in 1:2
 init!(slice(x, :, :, k)) # use slice to get SubArray 
end
</code></pre>

Note that you can use <code>ones(y)</code> to get a vector of ones of the same size as <code>y</code>.

A <code>SubArray</code> gives a view of an array, instead of a copy. In future versions of Julia, indexing an array may give this by default, but currently you must do it explicitly.

For a discussion about values vs. bindings, see

<a href="http://www.johnmyleswhite.com/notebook/2014/09/06/values-vs-bindings-the-map-is-not-the-territory/">http://www.johnmyleswhite.com/notebook/2014/09/06/values-vs-bindings-the-map-is-not-the-territory/</a>

EDIT: I hadn't seen @tholy's answer, which contains the same idea.

blocks|key|1002547|text|在Julia中发生了很多变化，我想我应该更新这个答案以反映Julia+1.5+(可能大多数更改是1.0)。虽然我希望现代的x[:,+:,+k]能够工作，因为它仍然被称为SubArray，实际上是在表达式中复制。相反，您必须使用view()|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1002548|x=+zeros(2,+2,+2)

function+init!(y)
++++y[:]=+ones(size(y))
end

init!(view(x,+:,+:,+1))+++#+get+reference+to+original+items|code-block|syntax|javascript|1002549|这将为您提供所需的结果：|1002550|julia>+x
2×2×2+Array{Float64,3}:
[:,+:,+1]+=
+1.0++1.0
+1.0++1.0

[:,+:,+2]+=
+0.0++0.0
+0.0++0.0|1002551|也有帮助器宏，用于以更容易接受的形式编写它，|1002552|init!(@view+x[:,:,1])|1002553|但是，如果您有其他论点，则可能会出现贪婪宏解析的危险，例如|1002554|otherfunc!(@view+x[:,:,1],+10)|1002555|会给你一个错误的Invalid+use+of+@view+macro:+argument+must+be+a+reference+expression。为了解决这个问题，有一个杂乱无章的@views，它把所有的_SubArray_s都变成视图，或者你也可以把参数放在括号里。|1002556|otherfunc!(@views+x[:,:,1],+10)
otherfunc!(@view(+x[:,:,1]),+10)|1002557|您可以在以下演示文稿中找到有关处理数组和矩阵的更多信息：(Youtube)+Arrays:+slices+and+views|1002558|entityMap|0|LINK|mutability|MUTABLE|url|https://www.youtube.com/watch?v=gTGJ80HayK0^0|1P|A|2C|8|35|6|0|0|0|0|0|0|0|0|8|1V|2L|6|0|0|S|Y|0|0^^$0|@$1|2|3|4|5|6|7|1A|8|@$9|1B|A|1C|B|C]|$9|1D|A|1E|B|C]|$9|1F|A|1G|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|1H|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|1I|8|@]|D|@]|E|$]]|$1|M|3|N|5|H|7|1J|8|@]|D|@]|E|$I|J]]|$1|O|3|P|5|6|7|1K|8|@]|D|@]|E|$]]|$1|Q|3|R|5|H|7|1L|8|@]|D|@]|E|$I|J]]|$1|S|3|T|5|6|7|1M|8|@]|D|@]|E|$]]|$1|U|3|V|5|H|7|1N|8|@]|D|@]|E|$I|J]]|$1|W|3|X|5|6|7|1O|8|@$9|1P|A|1Q|B|C]|$9|1R|A|1S|B|C]]|D|@]|E|$]]|$1|Y|3|Z|5|H|7|1T|8|@]|D|@]|E|$I|J]]|$1|10|3|11|5|6|7|1U|8|@]|D|@$9|1V|A|1W|1|1X]]|E|$]]|$1|12|3|-4|5|6|7|1Y|8|@]|D|@]|E|$]]]|13|$14|$5|15|16|17|E|$18|19]]]]

A lot has changed in Julia, and I thought I would update this answer to reflect Julia 1.5 (probably most of the changes were 1.0). While I would expect the modern <code>x[:, :, k]</code> to work, as this is still refered to as a <code>SubArray</code> this actually is copy now when in an expression. Instead you must use <code>view()</code>:
<pre><code>x= zeros(2, 2, 2)

function init!(y)
 y[:]= ones(size(y))
end

init!(view(x, :, :, 1)) # get reference to original items
</code></pre>
This gives you the desired result:
<pre><code>julia&gt; x
2×2×2 Array{Float64,3}:
[:, :, 1] =
 1.0 1.0
 1.0 1.0

[:, :, 2] =
 0.0 0.0
 0.0 0.0
</code></pre>
There are also helper macros for writing it in a more palatable form,
<pre><code>init!(@view x[:,:,1])
</code></pre>
but you run the danger of greedy macro parsing if you have other arguments, such that
<pre><code>otherfunc!(@view x[:,:,1], 10)
</code></pre>
would give you an error <code>Invalid use of @view macro: argument must be a reference expression</code>. To get around this, there is the kludge <code>@views</code> which turns all SubArrays into views, or you can wrap the argument in parenthesis.
<pre><code>otherfunc!(@views x[:,:,1], 10)
otherfunc!(@view( x[:,:,1]), 10)
</code></pre>
You can find more information on the manipulation of Arrays and Matrices in this presentation:
<a href="https://www.youtube.com/watch?v=gTGJ80HayK0" rel="nofollow noreferrer">(Youtube) Arrays: slices and views</a>

I have a three dimensional array defined as:

<pre><code>x=zeros(Float64,2,2,2)
</code></pre>

I want to assign ones to <code>x</code> by passing <code>x</code> to a function, one layer at a time.
The function is:

<pre><code>function init(p,y)
 y=ones(p,p)
end
</code></pre>

and I will pass <code>x</code> as follows:

<pre><code>for k=1:2
 init(2,x[2,2,k])
end
</code></pre>

but when I do that, <code>x</code> is zeros, not ones. Why?

<pre><code>julia&gt; x
2x2x2 Array{Float64,3}:
[:, :, 1] =
 0.0 0.0
 0.0 0.0

[:, :, 2] =
 0.0 0.0
 0.0 0.0
</code></pre>

Any idea how to get Julia to assign ones to <code>x</code>?

Passing two-dimensional array to a function in julia

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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我有一个三维数组，定义如下：x=zeros(Float64,2,2,2)我希望通过将x传递给一个函数，一次一层地将1赋给x。该函数为：function init(p,y)   y=ones(p,p)end我将按如下方式传递x：for k=1:2   init(2,x[2,2,k])end但是当我这样做的时候，x是0，而...

问将二维数组传递给julia中的函数
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