A semi-smart function for displaying tooltips with D3.js

## Functions

<dl>
<dt><a href="#showTooltip">showTooltip([parameters])</a></dt>
<dd><p>Shows a tooltip; assumes the existence of a div with <code>id=&quot;tooltip&quot;</code>, that is
positioned absolutely</p>
</dd>
<dt><a href="#hideTooltip">hideTooltip()</a></dt>
<dd><p>Shorthand for hiding the tooltip</p>
</dd>
</dl>

<a name="showTooltip"></a>

## showTooltip([parameters])
Shows a tooltip; assumes the existence of a div with `id="tooltip"`, that is
positioned absolutely

**Kind**: global function  

| Param | Type | Default | Description |
| --- | --- | --- | --- |
| [parameters] | <code>Object</code> | <code>{}</code> | Parameter object |
| [parameters.content] | <code>String</code> | <code>&#x27;&#x27;</code> | The message that will be displayed. Can be an empty string (hides the tooltip), a non-empty HTML string, or a function (which is called with the d3-selected tooltip div as the first argument) |
| [parameters.targetBounds] | <code>Object</code> | <code></code> | Specifies a bounding box that the tooltip should NOT occlude (typically, the results of a getBoundingClientRect() call) |
| [parameters.anchor] | <code>Object</code> | <code></code> | Specifies -1 to 1 positioning of the tooltip relative to targetBounds; for example, { x: -1 } right-aligns the tooltip to the left edge of targetBounds, { x: 0 } centers the tooltip horizontally, and { x: 1 } left-aligns the tooltip to the right edge of targetBounds |
| [parameters.hideAfterMs] | <code>Number</code> | <code>1000</code> | Hides the tooltip after a certain delay; set this to zero to disable hiding |

<a name="hideTooltip"></a>

## hideTooltip()
Shorthand for hiding the tooltip

**Kind**: global function