Calc normally displays numbers in decimal (base-10 or radix-10)
notation. Calc can actually display in any radix from two (binary) to 36.
When the radix is above 10, the letters
Z are used as
digits. When entering such a number, letter keys are interpreted as
potential digits rather than terminating numeric entry mode.
The key sequences d 2, d 8, d 6, and d 0 select binary, octal, hexadecimal, and decimal as the current display radix, respectively. Numbers can always be entered in any radix, though the current radix is used as a default if you press # without any initial digits. A number entered without a # is always interpreted as decimal.
To set the radix generally, use d r (
calc-radix) and enter
an integer from 2 to 36. You can specify the radix as a numeric prefix
argument; otherwise you will be prompted for it.
Integers normally are displayed with however many digits are necessary to
represent the integer and no more. The d z (
command causes integers to be padded out with leading zeros according to the
current binary word size. (See Binary Functions, for a discussion of
word size.) If the absolute value of the word size is ‘w’, all integers
are displayed with at least enough digits to represent
in the current radix. (Larger integers will still be displayed in their
Calc can display ‘w’-bit integers using two’s complement notation, although this is most useful with the binary, octal and hexadecimal display modes. This option is selected by using the O option prefix before setting the display radix, and a negative word size might be appropriate (see Binary Functions). In two’s complement notation, the integers in the (nearly) symmetric interval from ‘-2^(w-1)’ to ‘2^(w-1)-1’ are represented by the integers from ‘0’ to ‘2^w-1’: the integers from ‘0’ to ‘2^(w-1)-1’ are represented by themselves and the integers from ‘-2^(w-1)’ to ‘-1’ are represented by the integers from ‘2^(w-1)’ to ‘2^w-1’ (the integer ‘k’ is represented by ‘k+2^w’). Calc will display a two’s complement integer by the radix (either ‘2’, ‘8’ or ‘16’), two # symbols, and then its representation (including any leading zeros necessary to include all ‘w’ bits). In a two’s complement display mode, numbers that are not displayed in two’s complement notation (i.e., that aren’t integers from ‘-2^(w-1)’ to ‘2^(w-1)-1’) will be represented using Calc’s usual notation (in the appropriate radix).