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<title>JavaScript Math Object</title>
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<p>From <b>http://www.w3schools.com</b> (Copyright Refsnes Data)</p>
<h1>JavaScript Math Object</h1>
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<p class="intro">The Math object allows you to perform common mathematical
tasks.</p>
<hr />
<h2>Examples</h2>
<p><a target="_blank" href="../jsref/tryit.asp@filename=tryjsref_round">round()</a><br />
How to use round().</p>
<p><a target="_blank" href="../jsref/tryit.asp@filename=tryjsref_random">random()</a><br />
How to use random() to return a random number between 0 and 1.</p>
<p><a target="_blank" href="../jsref/tryit.asp@filename=tryjsref_max">max()</a><br />
How to use max() to return the number with the highest value of two specified numbers.</p>
<p><a target="_blank" href="../jsref/tryit.asp@filename=tryjsref_min">min()</a><br />
How to use min() to return the number with the lowest value of two specified numbers.</p>
<hr />
<h2>Complete Math Object Reference</h2>
<p>For a complete reference of all the properties and methods that can be used with
the Math object, go to our <a href="../jsref/jsref_obj_math.asp">
complete Math object reference</a>.</p>
<p>The reference contains a brief description and examples of use for each
property and method!</p>
<hr />
<h2>Math Object</h2>
<p>The Math object allows you to perform common mathematical tasks.</p>
<p>The Math object includes several mathematical values and functions. You
do not need to define the Math object before using it.</p>
<hr />
<h2>Mathematical Values</h2>
<p>JavaScript provides eight mathematical values (constants) that can be
accessed from the Math object. These are: E, PI, square root of 2, square root
of 1/2, natural log of 2, natural log of 10, base-2 log of E, and base-10 log of
E.</p>
<p>You may reference these values from your JavaScript like this:</p>
<table class="ex" cellspacing="0" border="1" width="100%" id="table11">
<tr>
<td>
<pre>Math.E
Math.PI
Math.SQRT2
Math.SQRT1_2
Math.LN2
Math.LN10
Math.LOG2E
Math.LOG10E</pre>
</td>
</tr>
</table>
<br />
<hr />
<h2>Mathematical Methods</h2>
<p>In addition to the mathematical values that can be accessed from the Math object
there are also several functions (methods) available.</p>
<p><b>Examples of functions (methods):</b></p>
<p>The following example uses the round() method of the Math object to
round a number to the nearest integer:</p>
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<td>
<pre>document.write(Math.round(4.7));</pre>
</td>
</tr>
</table>
<p>The code above will result in the following output:</p>
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<tr>
<td>
<pre>5</pre>
</td>
</tr>
</table>
<p>The following example uses the random() method of the Math object to
return a random number between 0 and 1:</p>
<table class="ex" cellspacing="0" border="1" width="100%" id="table5">
<tr>
<td>
<pre>document.write(Math.random());</pre>
</td>
</tr>
</table>
<p>The code above can result in the following output:</p>
<table class="ex" cellspacing="0" border="1" width="100%" id="table6">
<tr>
<td>
<pre><script type="text/javascript">
document.write(Math.random())
</script></pre>
</td>
</tr>
</table>
<p>The following example uses the floor() and random() methods of the Math object to
return a random number between 0 and 10:</p>
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<tr>
<td>
<pre>document.write(Math.floor(Math.random()*11));</pre>
</td>
</tr>
</table>
<p>The code above can result in the following output:</p>
<table class="ex" cellspacing="0" border="1" width="100%" id="table10">
<tr>
<td>
<pre><script type="text/javascript">
document.write(Math.floor(Math.random()*11))
</script></pre>
</td>
</tr>
</table>
<br />
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<p>From <b>http://www.w3schools.com</b> (Copyright Refsnes Data)</p>
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