You will find the answer yourself once you realize that there are two different things here:

- On the one hand there is the number of digits the calculator is working with. This may be something like 10, 12 or 16 digits, depending on the model. The calculator always uses this many digits for all its calculations, and all results have this precision.

- On the other hand there is the number of digits you want to see in the display. If you set FIX 2 you tell the calculator "just show me two decimals - I don't need to know the rest". This display setting only affects the number of digits you
*see*, while internally all values and results still have their full 10, 12 or 16 digits.

The round function now does this: it replaces the current full-precision value by the rounded number you see in the display. In other words: before, the number only was

*displayed* with two decimals, and afterwards it actually

*has* only two decimals.

Assume the current value is Pi = 3,141592653589793238462643... and your calculator works with 12 digits. This is what happens:

--- display set to ---

FIX 2 FIX 4

now

you see 3,14 3,1416 press 3,1416

[RND]

calculator 3,14159265359 3,14159265359 => 3,141600000000

works with

So in FIX the round function rounds to the chosen number of digits behind the decimal point. In SCI and ENG it rounds to the number of

*significant* digits you see. Finally try FIX 2, enter a value like 0,000004 and see what the round function does now.

Dieter

*Edited: 25 Apr 2011, 8:39 a.m. *