AnyDice provides two operations that allow you to query a value about its contents.

<h3>Length</h3>

You can perform the unary <code>#</code> operation to get the length of a value. What that means depends on the type of value involved.

<dl>
	<dt>Sequences</dt>
	<dd>The length of a sequence is equal to how many numbers is contains. So <code>#{2,4,6}</code> yields <code>3</code>.</dd>
	<dt>Collections of dice</dt>
	<dd>The length of a collection of dice is equal to the number of dice it contains. So <code>#(3d6)</code> yields <code>3</code>. Note the
	parentheses, without them it would be intepreted as <code>(#3)d6</code>, which would yield <code>1d6</code>.</dd>
	<dt>A single die</dt>
	<dd>A single die is considered to be a collection containing one die, so its length will always be <code>1</code>.</dd>
	<dt>Numbers</dt>
	<dd>The length of a number is equal to how many digits it has.</dd>
</dl>

<h3>Accessing</h3>

Using the <code>@</code> operation, you can retrieve individual numbers stored inside a value. You can either provide the position of a single
value to retrieve, or a sequence of positions, in which case the retrieved values are summed. If you ask for a position that does not exist,
the result for that position will be <code>0</code>.

<dl>
	<dt>Sequences</dt>
	<dd>For sequences, the number at the indicated position will be retrieved. So <code>1@{2,4,6}</code> yields <code>2</code>,
	<code>3@{2, 4, 6}</code> yields <code>6</code>, <code>{1,3}@{2,4,6}</code> yields <code>8</code>, and <code>{1,2,2}@{2,4,6}</code>
	yields <code>10</code>.</dd>
	<dt>Collections of dice</dt>
	<dd>When accessing collection of dice, the dice will be order from highest value to lowest value. So <code>1@3d6</code> will select the highest
	rolled value, while <code>3@3d6</code> will select the lowest rolled value. <code>{1,2}@3d6</code> will sum the highest two of the rolled values,
	discarding the lowest rolled value.	The result of the operation is a new die containing the selected
	values of all possible rolls and their appropriate odds.</dd>
	<dt>A single die</dt>
	<dd>A single die is considered to be a collection containing one die, so only the first positions will contain a useful value.</dd>
	<dt>Numbers</dt>
	<dd>For numbers, the digit at the indicated position will be retrieved, starting at the most significant – the leftmost – digit. So
	<code>1@246</code> yields <code>2</code>, while <code>{1..3}@246</code> yields <code>12</code>.</dd>
</dl>

If you want to, you can configure AnyDice to reverse the positions of dice in collections and of digits in numbers.

<code class="block">set "position order" to "lowest first"

output 1@3d6 named "lowest die"
output 1@246 named "least significant digit"

set "position order" to "highest first" \ the default behavior \

output 1@3d6 named "highest die"
output 1@246 named "most significant digit"</code>