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<table width="100%" summary="page for convertNative {grid}"><tr><td>convertNative {grid}</td><td align="right">R Documentation</td></tr></table>
<h2>Convert a Unit Object to Native units</h2>


<h3>Description</h3>

<p>
<B>This function is deprecated in grid version 0.8 and will be
made defunct in grid version 1.9</B>
</p>
<p>
You should use the <code>convertUnit()</code> function or one of its
close allies instead.
</p>
<p>
This function returns a numeric vector containing the specified
x or y locations or dimensions, converted to "user" or "data"
units, relative to the current viewport.
</p>


<h3>Usage</h3>

<pre>
convertNative(unit, dimension="x", type="location")
</pre>


<h3>Arguments</h3>

<table summary="R argblock">
<tr valign="top"><td><code>unit</code></td>
<td>
A unit object. </td></tr>
<tr valign="top"><td><code>dimension</code></td>
<td>
Either "x" or "y". </td></tr>
<tr valign="top"><td><code>type</code></td>
<td>
Either "location" or "dimension". </td></tr>
</table>

<h3>Value</h3>

<p>
A numeric vector.</p>

<h3>WARNING</h3>

<p>
If you draw objects based on output from these conversion
functions, then resize your device, the objects will be drawn 
incorrectly &ndash; the base R display list will not recalculate these
conversions.  This means that you can only rely on the results of 
these calculations if the size of your device is fixed.
</p>


<h3>Author(s)</h3>

<p>
Paul Murrell
</p>


<h3>See Also</h3>

<p>
<code><a href="grid.convert.html">grid.convert</a></code>, <code><a href="unit.html">unit</a></code>
</p>


<h3>Examples</h3>

<pre>
grid.newpage()
pushViewport(viewport(width=unit(.5, "npc"),
                       height=unit(.5, "npc")))
grid.rect()
w &lt;- convertNative(unit(1, "inches"))
h &lt;- convertNative(unit(1, "inches"), "y")
# This rectangle starts off life as 1in square, but if you
# resize the device it will no longer be 1in square
grid.rect(width=unit(w, "native"), height=unit(h, "native"),
          gp=gpar(col="red"))
popViewport(1)

# How to use grid.convert(), etc instead
convertNative(unit(1, "inches")) ==
  convertX(unit(1, "inches"), "native", valueOnly=TRUE)
convertNative(unit(1, "inches"), "y", "dimension") ==
  convertHeight(unit(1, "inches"), "native", valueOnly=TRUE)
</pre>



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