MACROMEDIA COLFUSION MX 7 - INSTALLING AND USING COLDFUSION MX, Reference

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744 Chapter 3: ColdFusion Functions
Log
Description
Calculates the natural logarithm of a number. Natural logarithms are based on the constant e
(2.71828182845904).
Returns
The natural logarithm of a number.
Category
Mathematical functions
Function syntax
Log ( number )
See also
Exp
,
Log10
Parameters
Example
<h3>Log Example</h3>
<cfif IsDefined("FORM.number")>
<cfoutput>
<p>Your number, #FORM.number#
<br>#FORM.number# raised to the E power: #exp(FORM.number)#
<cfif FORM.number LTE 0><br>Enter a positive real number to get its
natural logarithm
<cfelse><br>The natural logarithm of #FORM.number#: #log(FORM.number)#
</cfif>
<cfif FORM.number LTE 0><br>Enter a positive real number to get its
logarithm to base 10
<cfelse><br>The logarithm of #FORM.number# to base 10:
#log10(FORM.number)#
</cfif>
</cfoutput>
</cfif>
<cfform action = "log.cfm">
Enter a number to see its value raised to the E power, its natural logarithm,
and the logarithm of number to base 10.
<cfinput type = "Text" name = "number" message = "You must enter a number"
validate = "float" required = "No">
<input type = "Submit" name = "">
</cfform>
Parameter Description
number Positive real number for which to calculate the natural logarithm