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Asked by I Made on 27 Mar 2013

To put it simple my code similar to :

k=6 if(a/b<k) && (a/b>=0) STATEMENT1 elseif(a/b>-k) && (a/b<0) STATEMENT2 end

The problem is i got a/b = 0, so it should give me STATEMENT1 but i got STATEMENT 2, does anyone know how i can figure out my mistake?

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Answer by Walter Roberson on 27 Mar 2013

Try using the command

format long g

and then displaying a/b

It probably isn't really 0.

Answer by Jan Simon on 28 Mar 2013

Please read your question again and note, that Matlab does not perform any strange or magic actions. Then these two details:

1. if(a/b<k) && (a/b>=0) 2. The problem is i got a/b = 0, so it should give me STATEMENT1 but i got STATEMENT 2

imply, that either `a/b<k` is FALSE, or your assumption that `a/b==0` is wrong. A third possibility is, that you did not save the M-file after editing, such that Matlab does not run the program you currently see in the editor.

There are no other solutions. Walter's suggestion to increase the displayed precision is exhaustive to identify the problems.

## 3 Comments

Direct link to this comment:http://www.mathworks.com/matlabcentral/answers/68889#comment_139417

Did you try to check that

a/bis really close enough to0?what does that return ?

Direct link to this comment:http://www.mathworks.com/matlabcentral/answers/68889#comment_139419

i'm trying using that but little modification, like :

on the poin that segment(j,i) is 0 it return me 1 . but how could that possibly done? i checked the segment(j,i) at that point = 0, and the c(i) at that pint is 0,9375. So the result should be 0/0.9375==0 return me 0?

Direct link to this comment:http://www.mathworks.com/matlabcentral/answers/68889#comment_139424

Please try