Returns the natural logarithm of a complex number.

**Sample Usage**

IMLN("3+4i")

IMLN(C5)

**Syntax**

IMLN(complex_number)

- complex_number - The complex number whose natural logarithm is to be computed.

**Examples**

IMLN("3+4i") returns a value of 1.6094379124341+0.927295218001612i.

IMLN(C5) returns the natural logarithm of the complex number contained in C5.