How to get logarithm of base 10 value in Vijeo Designer software.

FA11612

23 January 2021

Only natural logarithm(of base e) is available under Math package of standard Java package version associated with Vijeo Designer software.

A workaround to calculate logarithm of base 10 is shown below:

Log base 10 = Math.log(x)/Math.log(10)

Log base 2 = Math.log(x)/Math.log(2) 

Given a number n greater than 0.0.

Then the log10(n) is equal to ln(n)/ln(10)(where "ln()" is the natural logarithm (base e))

If you store ln(10) as a constant, then you can get the log10(n) from ln(n) with one additional divide.

Example:

Given a number 'n' greater than 0.0 and a number 'b'greater than 0.0

Then the log<b>(n) is equal to ln(n)/ln(b)

where log<b>(n) means log value of (n) on base 'b' and "ln( )" is the natural logarithm (on base 'e')