MATLAB error in counting

How is it possible that my calculator comes out a different result than matlab calculated?

>> suma2= 7874;
voxsuma2=suma2*2*0.9766;
str = ['označena plocha je 2', num2str(voxsuma2), ' mm^2.']

str =

označena plocha je 215379.4968 mm^2.

a calculator:7874*2=15748

15748*0.9766=15379,4968

15379,4968 or 215379.4968 is correct? WTH??

[Adam]

good, as I do that the result was the same as on a calculator?

Answer 1

[Friedrich]

Hi

num2str is correct here, but the missing space after the 2 makes the result looking wrong, because the correct number 15379.4968 appears right after the 2. Try

suma2= 7874;
voxsuma2=suma2*2*0.9766;
str = ['označena plocha je 2 ', num2str(voxsuma2), ' mm^2.']

(Note the extra space after "je 2" before the num2str)

[Adam]

str = ['označena plocha je 2 ', num2str(voxsuma2), ' mm^2.']

do not understand why but when I removed the "2" so it goes well

str = ['označena plocha je',num2str(voxsuma2),'mm^2.'];

thank you much for the quick help and advice

[Friedrich]

Its a formatting thing, the num2str works correct. take the number you see on the screen 215379.4968 and ignore the 2 in front of it and you will get 15379.4968. The 2 you see is the 2 you print before it with the text string "je 2". Its like a typo. The 2 doenst belong to the value which num2str gives but it looks like it does.

Answer 2

[Ilham Hardy]

Just realized that!