MATLAB: One problem about rounding issue (but not the round function)

MATLABroundrounding

Hi everyone, I encounter one problem in one part of my program. To simpilfy, it's:
A = 1.495:0.1:2.495;
for i = 1:11
    disp(num2str(A(i),'%5.2f'));
end
it shows:
    1.50
    1.60
    1.70
    1.80
    1.90
    2.00
    2.10
    2.20
   →2.29
    2.40
    2.50
In a different machine it shows:
1.50
1.60
1.70
1.80
1.90
2.00
2.10
2.20
2.30
2.40
→2.49
This may be due to "the round function rounds away from zero to the integer with larger magnitude" in this link's sentence： https://ww2.mathworks.cn/help/matlab/ref/round.html?lang=en But I'm not sure. could anyone help me solve this problem, to let the program stably display correct rounding result? Many thanks.

Best Answer

Because of floating point errors, the "2.2950" is really 2.294999999999999999999999999999999999999, which rounds to 2.29. Do instead
A = round( 1.495:0.1:2.495  ,2);
or
 disp(num2str(round(  A(i)  ,2) ,'%5.2f'))
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