Campbell Scientific CR5000 Measurement and Control Module - Manual (Page 187)

Section 8. Processing and Math Instructions
8-15
Dim A, B, C, D 'Declare variables.
BeginProg
A = Int(-99.8)
'Returns -100
B = Fix(-99.8) 'Returns -99
C = Int(99.8) 'Returns 99
D = Fix(99.8) 'Returns 99
EndProg
Log (Source)
Returns the natural logarithm of a number.
Syntax
x = Log (source)
Remarks
The source can be any valid numeric expression that results in a value greater
than 0. The natural logarithm is the logarithm to the base e. The constant e is
approximately 2.718282.
You can calculate base-n logarithms for any number x by dividing the natural
logarithm of x by the natural logarithm of n as follows:
Logn(x) = Log(x) / Log(n)
The following example illustrates a procedure that calculates base-10
logarithms:
Log10 = Log(X) / Log(10)
Log Function Example
The example calculates the value of e, then uses the Log function to calculate
the natural logarithm of e to the first, second, and third powers.
Dim I, M 'Declare variables.
BeginProg
M = Exp(1)
For I = 1 To 3
'Do three times.
M =Log(Exp(1) ^ I)
Next I
EndProg
LOG10 (number)
The LOG10 function returns the base 10 logarithm of a number.
Syntax
LOG10( number )
Remarks
The LOG10 function returns the logarithm base 10 of a number.
The Number argument can be any valid numeric expression that has a value
greater than 0. You can calculate base-n logarithms for any number x by
dividing the logarithm base 10 of x by the logarithm base 10 of n as follows: