The C-x * k
(calc-keypad) command starts the Calculator and
displays a picture of a calculator-style keypad. If you are using
the X window system, you can click on any of the
“keys” in the keypad using the left mouse button to
operate the calculator. The original window remains the selected
window; in Keypad mode you can type in your file while
simultaneously performing calculations with the mouse.
If you have used
C-x * b first, C-x * k instead invokes the
full-calc-keypad command, which takes over the whole
Emacs screen and displays the keypad, the Calc stack, and the
Calc trail all at once. This mode would normally be used when
running Calc standalone (see Standalone
Operation).
If you aren't using the X window system, you must switch into the ‘*Calc Keypad*’ window, place the cursor on the desired “key,” and type <SPC> or <RET>. If you think this is easier than using Calc normally, go right ahead.
Calc commands are more or less the same in Keypad mode. Certain keypad keys differ slightly from the corresponding normal Calc keystrokes; all such deviations are described below.
Keypad mode includes many more commands than will fit on the
keypad at once. Click the right mouse button
[calc-keypad-menu] to switch to the next menu. The
bottom five rows of the keypad stay the same; the top three rows
change to a new set of commands. To return to earlier menus,
click the middle mouse button
[calc-keypad-menu-back] or simply advance through
the menus until you wrap around. Typing <TAB> inside the
keypad window is equivalent to clicking the right mouse button
there.
You can always click the <EXEC> button and type any normal Calc key sequence. This is equivalent to switching into the Calc buffer, typing the keys, then switching back to your original buffer.