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<h1 id="function-leafcount">Function leafCount <a href="#function-leafcount" title="Permalink">#</a></h1>

Gives the number of "leaf nodes" in the parse tree of the given expression
A leaf node is one that has no subexpressions, essentially either a
symbol or a constant. Note that `5!` has just one leaf, the '5'; the
unary factorial operator does not add a leaf. On the other hand,
function symbols do add leaves, so `sin(x)/cos(x)` has four leaves.

The `simplify()` function should generally not increase the `leafCount()`
of an expression, although currently there is no guarantee that it never
does so. In many cases, `simplify()` reduces the leaf count.


<h2 id="syntax">Syntax <a href="#syntax" title="Permalink">#</a></h2>

```js
math.leafCount(expr)
```

<h3 id="parameters">Parameters <a href="#parameters" title="Permalink">#</a></h3>

Parameter | Type | Description
--------- | ---- | -----------
`expr` | Node &#124; string | The expression to count the leaves of

<h3 id="returns">Returns <a href="#returns" title="Permalink">#</a></h3>

Type | Description
---- | -----------
number | The number of leaves of `expr`


<h3 id="throws">Throws <a href="#throws" title="Permalink">#</a></h3>

Type | Description
---- | -----------


<h2 id="examples">Examples <a href="#examples" title="Permalink">#</a></h2>

```js
math.leafCount('x') // 1
math.leafCount(math.parse('a*d-b*c')) // 4
math.leafCount('[a,b;c,d][0,1]') // 6
```


<h2 id="see-also">See also <a href="#see-also" title="Permalink">#</a></h2>

[simplify](simplify.html)