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>