2 - 2.01 ??

[Michal Sza]

Hey,
How come 2 - 2.01 = -0.00999999999999979 and not -0.01
???
Can someone explain this to me please?

 

[Jano Svitok]

Hey,
How come 2 - 2.01 = -0.00999999999999979 and not -0.01
???
Can someone explain this to me please?

http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-talk/273263

 

[Tim Hunter]

Hey,
How come 2 - 2.01 = -0.00999999999999979 and not -0.01
???
Can someone explain this to me please?

Because 0.01 cannot be represented accurately in binary. See
http://en.wikipedia.org/wiki/Floating_point#Accuracy_problems.

 

[Gregory Seidman]

Hey,
How come 2 - 2.01 = -0.00999999999999979 and not -0.01
???
Can someone explain this to me please?

http://en.wikipedia.org/wiki/Floating_point#Accuracy_problems

--Greg

 

[Karl von Laudermann]

Hey,
How come 2 - 2.01 = -0.00999999999999979 and not -0.01
???
Can someone explain this to me please?

This question comes up a lot. Google "floating point errors" for some
good links.

 

[Guest]

Hey,
How come 2 - 2.01 = -0.00999999999999979 and not -0.01
???
Can someone explain this to me please?

Because you are using floating point.

Reas this article for an explanation:

"What Every Computer Scientist Should Know About Floating-Point Arithmetic"

http://docs.sun.com/source/806-3568/ncg_goldberg.html

Kristian