Returns the natural logarithm of a specified number. Natural logarithms are based on the constant e value of 2.71828182845904.
Use
LN(number) and replace
number with the field or expression for which you want the natural
logarithm. Note: the LN function is the inverse of the EXP function.
Formula Example
LN(10) returns the natural logarithm of 10, which is
2.30.
LN(Value__c) returns the natural logarithm of a custom
number field called Value.