Why does following code don't give any output?

for i =0.1:0.1:12

if(i==3)

fprintf('Hello\n')

end

end

Answer 1

[Rik]

Because the number 3 doesn't exist in your array:

data=0.1:0.1:12;
[~,ind]=min(abs(data-3));
data(ind)

ans = 3.0000

Now, that looks like 3, but let's investigate if it is exactly 3:

data(ind)-3

ans = 4.4409e-16

Close, but not exact. Since you used ==, Matlab will only give you the fprintf if the match is exact.

The solution is to use a tolerance.

for i =0.1:0.1:12
    if abs(i-3)<(10*eps)
        fprintf('Hello\n')
    end
end

Hello