<doc>
  <legacy_id>2091</legacy_id>
  <name>ln</name>
  <type>function</type>
  <syntax>
    <example>the ln of <i>number</i></example>
    <example>ln(<i>number</i>)</example>
  </syntax>
  <library></library>
  <objects>
  </objects>
  <synonyms>
  </synonyms>
  <classification>
    <category>Math, Logic, &amp; Dates</category>
  </classification>
  <references>
    <function tag="ln1">ln1 Function</function>
    <function tag="exp">exp Function</function>
  </references>
  <history>
    <introduced version="1.0">Added.</introduced>
  </history>
  <platforms>
    <mac/>
    <windows/>
    <linux/>
    <ios/>
    <android/>
  </platforms>
  <classes>
    <desktop/>
    <server/>
    <web/>
    <mobile/>
  </classes>
  <security>
  </security>
  <summary><glossary tag="return">Returns</glossary> the natural logarithm of a number.</summary>
  <examples>
    <example>ln(1) <code><i>-- returns zero</i></code></example>
    <example>ln(0.15) <code><i>-- returns -1.89712</i></code></example>
    <example>ln(10) <code><i>-- returns 2.302585</i></code></example>
  </examples>
  <description>
    <p>Use the <b>ln</b> function to obtain a base e logarithm.</p><p/><p><b>Parameters:</b></p><p>The <i>number</i> is a positive number, or an <glossary tag="expression">expression</glossary> that <glossary tag="evaluate">evaluates</glossary> to a positive number.</p><p/><p><b>Value:</b></p><p>The <b>ln</b> <control_st tag="function">function</control_st> <glossary tag="return">returns</glossary> a number.</p><p/><p><b>Comments:</b></p><p>The natural logarithm of a <i>number</i> is the power to which e must be raised to obtain the <i>number</i>.</p><p/><p>The transcendental number e appears in many mathematical formulas.</p><p/><p>To find the logarithm of a number in any base, use the following function:</p><p/><p><code>  function logarithm theBase,theNumber</code></p><p><code/>    return ln(theNumber)/ln(theBase)</p><p><code>  end logarithm</code></p>
  </description>
</doc>