matlab negative and positive infinity problem

8 views (last 30 days)
hi there,
I am quite confused about how matlab deals with inf and -inf. Here is the problem I confronted
x0p = 0;
b = 0.0050;
y0p =0;
(x0p-b)/y0p
ans =
Inf
But it should be -inf. I changed the value of b but still got the same answer. I tried using numbers directly and it seems correct as shown below. I don't know the mechanism behind it. So I hope someone could help me figure it out.
-1/0
ans =
-Inf
Cheers,
Jianan
  3 Comments
Walter Roberson
Walter Roberson on 4 May 2019
-Inf is what shows up for me in R2019a. Which version are you using, on which operating system?
I suggest you use num2hex(x0p) and y0p to verify that they are true zeros. Also, store the result in a variable and use num2hex() on it. -inf is fff followed by all 0, and +inf is 7ff followed by all 0.
Jianan He
Jianan He on 4 May 2019
Thanks guys, I found my problem. I didn't realize that zero can be negative or positive in matlab.
sprintf('%.32f',y0p)
ans =
'-0.00000000000000000000000000000000'
Thanks again, it's my first time asking questions in community and I appreciate your guys help!

Sign in to comment.

Answers (0)

Categories

Find more on Mathematics in Help Center and File Exchange

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!