Internal Representation of Numeric Values
Any numeric value you enter using one of the formatted modes (including hex and octal) is converted for internal use as a floating-point decimal number. No such conversion takes place for bytes you enter using the unformatted mode.
Floating-Point Representation
Numeric values are stored internally as three components:- A 13-digit mantissa (with an assumed decimal point following the first digit).
- A sign digit
- A two-digit exponent.
For example, the number -0.64 is stored as:
The sign digit may be one of four values, depending on the sign of the mantissa and the sign of the exponent. (Values other than those shown here are not used or indicate an error condition.)
Sign Digit | Meaning |
|---|---|
| 0 | Positive mantissa, positive exponent |
| 4 | Negative mantissa, positive exponent |
| 8 | Positive mantissa, negative exponent |
| C | Negative mantissa, negative exponent |
Example
Use the unformatted mode to show the internal, floating-point representation of a decimal number.Procedure | Press | Display |
|---|---|---|
| Enter a number | .64 [ +/- ] |  |
| Display internal representation | [ CONV ] { BAS } { UNF } |  |
| Return to decimal mode | { DEC } |  |
In the unformatted mode, the sign digit C indicates that both the mantissa and exponent are negative. Therefore, the mantissa is -6.400000000000 and the exponent is -01, which is equivalent to -0.64.
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