LNP1

Member Of Menu: 
Logs
Argument Types: 
Real
Symbol
Expression
Result Type(s): 
Real
Expression
Invertible: 
Yes
Valid In Expression: 
Yes
Stack Diagram: 
Real1 → Real2
Symbol1 → Expression2
Expression1 → Expression2

This operation calculates the equivalent of LN(1 + x) where x is the the argument from the stack. It may appear to be redundant since the LN operation seems to be capable of everything this operation can do, and more but this operation is much more accurate for values near 0 (ie near 1 for LN). So, in some cases, this operation is preferred.

However, this operation is more limited. It does not handle complex numbers and will fail for any input value of -1 or less.