NAME
xcalc - scientific calculator for X
SYNOPSIS
xcalc [-stipple] [-rpn] [-toolkitoption...]
DESCRIPTION
xcalc is a scientific calculator desktop accessory that can emulate a
TI-30 or an HP-10C.
OPTIONS
xcalc accepts all of the standard toolkit command line options along
with two additional options:
-stipple
This option indicates that the background of the calculator
should be drawn using a stipple of the foreground and
background colors. On monochrome displays improves the
appearance.
-rpn This option indicates that Reverse Polish Notation should be
used. In this mode the calculator will look and behave like an
HP-10C. Without this flag, it will emulate a TI-30.
OPERATION
Pointer Usage: Operations may be performed with pointer button 1, or in
some cases, with the keyboard. Many common calculator operations have
keyboard accelerators. To quit, press pointer button 3 on the AC key
of the TI calculator, or the ON key of the HP calculator.
Calculator Key Usage (TI mode): The numbered keys, the +/- key, and the
+, -, *, /, and = keys all do exactly what you would expect them to.
It should be noted that the operators obey the standard rules of
precedence. Thus, entering "3+4*5=" results in "23", not "35". The
parentheses can be used to override this. For example,
"(1+2+3)*(4+5+6)=" results in "6*15=90".
The entire number in the calculator display can be selected, in order
to paste the result of a calculation into text.
The action procedures associated with each function are given below.
These are useful if you are interested in defining a custom calculator.
The action used for all digit keys is digit(n), where n is the
corresponding digit, 0..9.
1/x Replaces the number in the display with its reciprocal. The
corresponding action procedure is reciprocal().
x^2 Squares the number in the display. The corresponding action
procedure is square().
SQRT Takes the square root of the number in the display. The
corresponding action procedure is squareRoot().
CE/C When pressed once, clears the number in the display without
clearing the state of the machine. Allows you to re-enter a
number if you make a mistake. Pressing it twice clears the
state, also. The corresponding action procedure for TI mode
is clear().
AC Clears the display, the state, and the memory. Pressing it
with the third pointer button turns off the calculator, in
that it exits the program. The action procedure to clear the
state is off(); to quit, quit().
INV Invert function. See the individual function keys for
details. The corresponding action procedure is inverse().
sin Computes the sine of the number in the display, as
interpreted by the current DRG mode (see DRG, below). If
inverted, it computes the arcsine. The corresponding action
procedure is sine().
cos Computes the cosine, or arccosine when inverted. The
corresponding action procedure is cosine().
tan Computes the tangent, or arctangent when inverted. The
corresponding action procedure is tangent().
DRG Changes the DRG mode, as indicated by ’DEG’, ’RAD’, or ’GRAD’
at the bottom of of the calculator ‘‘liquid crystal’’
display. When in ’DEG’ mode, numbers in the display are
taken as being degrees. In ’RAD’ mode, numbers are in
radians, and in ’GRAD’ mode, numbers are in grads. When
inverted, the DRG key has a feature of converting degrees to
radians to grads and vice-versa. Example: put the
calculator into ’DEG’ mode, and enter "45 INV DRG". The
display should now show something along the lines of
".785398", which is 45 degrees converted to radians. The
corresponding action procedure is degree().
e The constant ’e’. (2.7182818...). The corresponding action
procedure is e().
EE Used for entering exponential numbers. For example, to get
"-2.3E-4" you’d enter "2 . 3 +/- EE 4 +/-". The
corresponding action procedure is scientific().
log Calculates the log (base 10) of the number in the display.
When inverted, it raises "10.0" to the number in the display.
For example, entering "3 INV log" should result in "1000".
The corresponding action procedure is logarithm().
ln Calculates the log (base e) of the number in the display.
When inverted, it raises "e" to the number in the display.
For example, entering "e ln" should result in "1". The
corresponding action procedure is naturalLog().
y^x Raises the number on the left to the power of the number on
the right. For example "2 y^x 3 =" results in "8", which is
2^3. For a further example, "(1+2+3) y^x (1+2) =" equals "6
y^x 3" which equals "216". The corresponding action
procedure is power().
PI The constant ’pi’. (3.1415927....) The corresponding action
procedure is pi().
x! Computes the factorial of the number in the display. The
number in the display must be an integer in the range 0-500,
though, depending on your math library, it might overflow
long before that. The corresponding action procedure is
factorial().
( Left parenthesis. The corresponding action procedure for TI
calculators is leftParen().
) Right parenthesis. The corresponding action procedure for TI
calculators is rightParen().
/ Division. The corresponding action procedure is divide().
* Multiplication. The corresponding action procedure is
multiply().
- Subtraction. The corresponding action procedure is
subtract().
+ Addition. The corresponding action procedure is add().
= Perform calculation. The TI-specific action procedure is
equal().
STO Copies the number in the display to the memory location. The
corresponding action procedure is store().
RCL Copies the number from the memory location to the display.
The corresponding action procedure is recall().
SUM Adds the number in the display to the number in the memory
location. The corresponding action procedure is sum().
EXC Swaps the number in the display with the number in the memory
location. The corresponding action procedure for the TI
calculator is exchange().
+/- Negate; change sign. The corresponding action procedure is
negate().
. Decimal point. The action procedure is decimal().
Calculator Key Usage (RPN mode): The number keys, CHS (change sign), +,
-, *, /, and ENTR keys all do exactly what you would expect them to do.
Many of the remaining keys are the same as in TI mode. The differences
are detailed below. The action procedure for the ENTR key is enter().
<- This is a backspace key that can be used if you make a
mistake while entering a number. It will erase digits from
the display. (See BUGS). Inverse backspace will clear the X
register. The corresponding action procedure is back().
ON Clears the display, the state, and the memory. Pressing it
with the third pointer button turns off the calculator, in
that it exits the program. To clear state, the action
procedure is off; to quit, quit().
INV Inverts the meaning of the function keys. This would be the
f key on an HP calculator, but xcalc does not display
multiple legends on each key. See the individual function
keys for details.
10^x Raises "10.0" to the number in the top of the stack. When
inverted, it calculates the log (base 10) of the number in
the display. The corresponding action procedure is
tenpower().
e^x Raises "e" to the number in the top of the stack. When
inverted, it calculates the log (base e) of the number in the
display. The action procedure is epower().
STO Copies the number in the top of the stack to a memory
location. There are 10 memory locations. The desired memory
is specified by following this key with a digit key.
RCL Pushes the number from the specified memory location onto the
stack.
SUM Adds the number on top of the stack to the number in the
specified memory location.
x:y Exchanges the numbers in the top two stack positions, the X
and Y registers. The corresponding action procedure is
XexchangeY().
R v Rolls the stack downward. When inverted, it rolls the stack
upward. The corresponding action procedure is roll().
blank These keys were used for programming functions on the HP-10C.
Their functionality has not been duplicated in xcalc.
Finally, there are two additional action procedures: bell(), which
rings the bell; and selection(), which performs a cut on the entire
number in the calculator’s ‘‘liquid crystal’’ display.
ACCELERATORS
Accelerators are shortcuts for entering commands. xcalc provides some
sample keyboard accelerators; also users can customize accelerators.
The numeric keypad accelerators provided by xcalc should be intuitively
correct. The accelerators defined by xcalc on the main keyboard are
given below:
TI Key HP Key Keyboard Accelerator TI Function HP Function
SQRT SQRT r squareRoot() squareRoot()
AC ON space clear() clear()
AC <- Delete clear() back()
AC <- Backspace clear() back()
AC <- Control-H clear() back()
AC Clear clear()
AC ON q quit() quit()
AC ON Control-C quit() quit()
INV i i inverse() inverse()
sin s s sine() sine()
cos c c cosine() cosine()
tan t t tangent() tangent()
DRG DRG d degree() degree()
e e e()
ln ln l naturalLog() naturalLog()
y^x y^x ^ power() power()
PI PI p pi() pi()
x! x! ! factorial() factorial()
( ( leftParen()
) ) rightParen()
/ / / divide() divide()
* * * multiply() multiply()
- - - subtract() subtract()
+ + + add() add()
= = equal()
0..9 0..9 0..9 digit() digit()
. . . decimal() decimal()
+/- CHS n negate() negate()
x:y x XexchangeY()
ENTR Return enter()
ENTR Linefeed enter()
CUSTOMIZATION
The application class name is XCalc.
xcalc has an enormous application defaults file which specifies the
position, label, and function of each key on the calculator. It also
gives translations to serve as keyboard accelerators. Because these
resources are not specified in the source code, you can create a
customized calculator by writing a private application defaults file,
using the Athena Command and Form widget resources to specify the size
and position of buttons, the label for each button, and the function of
each button.
The foreground and background colors of each calculator key can be
individually specified. For the TI calculator, a classical color
resource specification might be:
XCalc.ti.Command.background: gray50
XCalc.ti.Command.foreground: white
For each of buttons 20, 25, 30, 35, and 40, specify:
XCalc.ti.button20.background: black
XCalc.ti.button20.foreground: white
For each of buttons 22, 23, 24, 27, 28, 29, 32, 33, 34, 37, 38, and 39:
XCalc.ti.button22.background: white
XCalc.ti.button22.foreground: black
WIDGET HIERARCHY
In order to specify resources, it is useful to know the hierarchy of
the widgets which compose xcalc. In the notation below, indentation
indicates hierarchical structure. The widget class name is given
first, followed by the widget instance name.
XCalc xcalc
Form ti or hp (the name depends on the mode)
Form bevel
Form screen
Label M
Toggle LCD
Label INV
Label DEG
Label RAD
Label GRAD
Label P
Command button1
Command button2
Command button3
and so on, ...
Command button38
Command button39
Command button40
APPLICATION RESOURCES
rpn (Class Rpn)
Specifies that the rpn mode should be used. The default is TI
mode.
stipple (Class Stipple)
Indicates that the background should be stippled. The default
is ‘‘on’’ for monochrome displays, and ‘‘off’’ for color
displays.
cursor (Class Cursor)
The name of the symbol used to represent the pointer. The
default is ‘‘hand2’’.
COLORS
If you would like xcalc to use its ti colors, include the following in
the #ifdef COLOR section of the file you read with xrdb:
*customization: -color
This will cause xcalc to pick up the colors in the app-defaults color
customization file: /etc/X11/app-defaults/XCalc-color.
SEE ALSO
X(7), xrdb(1), the Athena Widget Set
BUGS
HP mode is not completely debugged. In particular, the stack is not
handled properly after errors.
COPYRIGHT
Copyright 1994 X Consortium
See X(7) for a full statement of rights and permissions.
AUTHORS
John Bradley, University of Pennsylvania
Mark Rosenstein, MIT Project Athena
Donna Converse, MIT X Consortium