How this expr command works in TCL

Question

set number [expr {int(1.2/0.1)}] 
puts $number

from the above am getting output as

"11"

Could someone explain how am getting this result using TCL

score 4 · Answer 1 · edited May 23 '17 at 12:28

4

That's because 1.2/0.1 is 11.999999999999998. And int() takes only the integer portion and discards the .999999999999998 part. So the answer becomes 11.

As for why it's 11.999999999999998, that's the behavior of floating point numbers. There's lots of questions on SO and on other parts of the internet about this so I'm going to point you to just one question: Is floating point math broken?

edited May 23 '17 at 12:28

Community

1
1

answered Feb 17 '15 at 08:44

slebetman

109,858
19
140
171

You should also read this: http://docs.oracle.com/cd/E19957-01/806-3568/ncg_goldberg.html – slebetman Feb 17 '15 at 08:46

How this expr command works in TCL

1 Answers1