Strange loop on Java for 0.1 to 2

Question

I tried to loop from 0.1 to 2.0 and then print the output to the console.. But I got strange output like these:

0.1
0.2
0.30000000000000004
0.4
0.5
0.6
0.7
0.7999         


        

Answer 1

That's a bug (on your side).

Do not use floating point numbers until you learn what they are and how they work.

Answer 2

This is normal. It's inherent in floating point; numbers like 0.3 can't be stored as exact values in binary, so you get slowly accumulating errors. References: Python manual, Wikipedia, Technical explanation from Princeton CS.