EVOLUTION-MANAGER

Edit File: array-coercion.html

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<table width="100%" summary="page for array-coercion {purrr}"><tr><td>array-coercion {purrr}</td><td style="text-align: right;">R Documentation</td></tr></table>

<h2>Coerce array to list</h2>

<h3>Description</h3>

<p><code>array_branch()</code> and <code>array_tree()</code> enable arrays to be
used with purrr's functionals by turning them into lists. The
details of the coercion are controlled by the <code>margin</code>
argument. <code>array_tree()</code> creates an hierarchical list (a tree)
that has as many levels as dimensions specified in <code>margin</code>,
while <code>array_branch()</code> creates a flat list (by analogy, a
branch) along all mentioned dimensions.
</p>

<h3>Usage</h3>

<pre>
array_branch(array, margin = NULL)

array_tree(array, margin = NULL)
</pre>

<h3>Arguments</h3>

<table summary="R argblock">
<tr valign="top"><td><code>array</code></td>
<td>
<p>An array to coerce into a list.</p>
</td></tr>
<tr valign="top"><td><code>margin</code></td>
<td>
<p>A numeric vector indicating the positions of the
indices to be to be enlisted. If <code>NULL</code>, a full margin is
used. If <code>numeric(0)</code>, the array as a whole is wrapped in a
list.</p>
</td></tr>
</table>

<h3>Details</h3>

<p>When no margin is specified, all dimensions are used by
default. When <code>margin</code> is a numeric vector of length zero, the
whole array is wrapped in a list.
</p>

<h3>Examples</h3>

<pre>
# We create an array with 3 dimensions
x &lt;- array(1:12, c(2, 2, 3))

# A full margin for such an array would be the vector 1:3. This is
# the default if you don't specify a margin

# Creating a branch along the full margin is equivalent to
# as.list(array) and produces a list of size length(x):
array_branch(x) %&gt;% str()

# A branch along the first dimension yields a list of length 2
# with each element containing a 2x3 array:
array_branch(x, 1) %&gt;% str()

# A branch along the first and third dimensions yields a list of
# length 2x3 whose elements contain a vector of length 2:
array_branch(x, c(1, 3)) %&gt;% str()

# Creating a tree from the full margin creates a list of lists of
# lists:
array_tree(x) %&gt;% str()

# The ordering and the depth of the tree are controlled by the
# margin argument:
array_tree(x, c(3, 1)) %&gt;% str()
</pre>

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