How to count the number of digits of a floating number?

[Chrisir]

via String

float a1= 12.345678; 

println (a1);
String s1 = str(a1);
println (s1);
int pointPos = s1.indexOf("."); 
String s2 = s1.substring(pointPos+1, s1.length());
println(s2);
println(s2.length());