ENG display mode on HP-15C

[RPNerd]

(08-22-2024 07:33 PM)Pekis Wrote:  The BIG problem with that insertion is that it makes you believe that 200 E0 is the result of rounding to the last digit (coming from 199.5 E0, or 200.4 E0, ...), which is not the case !

Like any form of computer, the calculator does what you tell it to do, which is not necessarily what you want it to do. By using ENG 0 you are telling the calculator that you don't want any digits after the mantissa's decimal point and that's what you're being given. If that's not what you want then you have to tell the calculator to give you something different.

Remember, 178 is stored internally as 1.78×10². The mantissa is 1.78. With no digits after the decimal point, it's going to get rounded up to 2 and ENG notation only affects how that number is being displayed.