log10
This function returns the common (base-10) logarithm of x.
double log10(double x)
Parameters:
x
The number to convert.
Return value:
Common logarithm of x, for values of x greater than zero. If x is 0 or less, the function will return 0.
Remarks:
None.
Example:

    void main()
    {
    double param=1000.0;
    double result=log10(param);
    alert("log10 test", "log10 "+param+" is "+result+".");
    }