Computations:

The operators are all single-character:

+

begins an addition

-

begins a subtraction

~

negates the result

*

begins a multiplication

/

begins a division

%

begins an interest computation (uses interval): rate=number.

$

begins a sales-tax computation: rate=number.

(

opening parenthesis. This may enclose a unary '-', more parentheses, or data (implicit unary '+').

)

closing parenthesis, expects another operator, not data.

=

flushes out the current number, forces re-computation of the running result.

A space flushes out the current number-input, and (by default) sets the next operator to be the same as the current one. You may repeat the last arithmetic operation of any type:

a

repeats the last '+' (default 0).

s

repeats the last '-' (default 0).

n

repeats the last '~'.

m

repeats the last '*' (default 1).

d

repeats the last '/' (default 1).

i

repeats the last '%' (default 4).

t

repeats the last '$' (default 4).

You may toggle the prefix operator of any number by typing a single character:

A

toggles the operator to '+'.

S

toggles the operator to '-'.

N

toggles the operator to '~'.

M

toggles the operator to '*'.

D

toggles the operator to '/'.

I

toggles the operator to '%'.

T

toggles the operator to '$'.

Editing:

As you enter data, you may edit it. A backspace deletes the last digit of the current number (if it is visible). Use the arrow keys or vi-style 'h' and 'l' to move left and right within the line. Other editing commands include

u

undoes the last x/X command (restricted to restoring the current data only).

x

deletes the current data. If the data is null, deletes the following line.

X

deletes the current data. If the data is null, deletes the preceding line and moves up.

o

opens a new line after the current line.

O

opens a new line before the current line.

#

edit the associated comment.

An "open" permits you to insert a new operator and data into the expression list. You may type an operator character (e.g., '+'), and continue with the new data, or an operator-repeat (e.g., 'A'). In either case, you may edit the new data, just as you would the old data. A 'u' (or other toggle, such as 'o', 'O', or 'q') typed after an open will undo the open (and close it).

Scrolling/cursor movement:

H

move to the top line on the screen.

M

move to the middle line on the screen.

L

move to the last line on the screen

CTL/F

scroll forward one screen.

CTL/B

scroll backward one screen.

j

move forward one line.

k

move backward one line.

z<CR>

move the current line to the top of the screen.

z.

move the current line to the middle of the screen.

z-

move the current line to the bottom of the screen.

Like vi, tapecalc allows you to jump to a particular line with a ":" command

:$

jumps to the last entry

:1

jumps to the first entry.

Scripts:

Transcript files are formatted to permit line-oriented entries:

<operator><value><tab><ignored><tab># comment

The transcripts saved by tapecalc contain the running result in the "ignored" part. To exit without saving a transcript, type 'Q'. A normal exit, by typing 'q', saves the list of operators, data (and running result) in the specified file.

You can read and write scripts without leaving tapecalc. reads a script at the current entry

:e file

clears the current script and reads a script from the file.

:f

shows the current script name.

:r file

:w file

writes a script to the specified file.