Data Type: Double
A numeric expression greater than zero.
Returns the natural logarithm of a given number.
The natural logarithm is based on
e, a constant whose value is
approximately 2.718282. The natural logarithm is expressed by
ez = x
Log(x). In other words, the natural
logarithm is the inverse of the exponential function.
number, the value whose natural
logarithm the function is to return, must be a positive real
number. If number is negative or zero, the function generates
runtime error 5, “Invalid procedure call or argument.”
You can calculate base-
logarithms for any number
dividing the natural logarithm of
by the natural logarithm of
n, as the
following expression illustrates:
x) = Log(
x) / Log(
For example, the Log10 function shows the source code for a custom function that calculates base-10 logarithms:
Function Log10(X) Log10 = Log(X) / Log(10) End Function
A number of other mathematical functions that aren’t intrinsic to VBScript can be computed using the value returned by the Log function. The functions and their formulas are: