Orpie v1.5 User Manual

Paul J. Pelzl

September 13, 2007

“Because the equals key is for the weak.”

Contents

1  Introduction

Orpie is a console-based RPN (reverse polish notation) desktop calculator. The interface is similar to that of modern Hewlett-PackardTM calculators, but has been optimized for efficiency on a PC keyboard. The design is also influenced to some degree by the Mutt email client and the Vim editor.

Orpie does not have graphing capability, nor does it offer much in the way of a programming interface; other applications such as GNU Octave. are already very effective for such tasks. Orpie focuses specifically on helping you to crunch numbers quickly.

Orpie is written in Objective Caml (aka OCaml), a high-performance functional programming language with a whole lot of nice features. I highly recommend it.

2  Installation

This section describes how to install Orpie by compiling from source. Volunteers have pre-packaged Orpie for several popular operating systems, so you may be able to save yourself some time by installing from those packages. Please check the Orpie website for up-to-date package information.

Before installing Orpie, you should have installed the GNU Scientific Library (GSL) version 1.4 or greater. You will also need a curses library (e.g. ncurses), which is almost certainly already installed on your system. Finally, OCaml 3.07 or higher is required to compile the sources. You will need the Nums library that is distributed with OCaml; if you install OCaml from binary packages distributed by your OS vendor, you may find that separate Nums packages must also be installed.

I will assume you have received this program in the form of a source tarball, e.g. “orpie-x.x.tar.gz”. You have undoubtedly extracted this archive already (e.g. using “tar xvzf orpie-x.x.tar.gz”). Enter the root of the Orpie installation directory, e.g. “cd orpie-x.x”. You can compile the sources with the following sequence:

$ ./configure
$ make

Finally, run “make install” (as root) to install the executables. “configure” accepts a number of parameters that you can learn about with “./configure –help”. Perhaps the most common of these is the –prefix option, which lets you install to a non-standard directory1.

3  Quick Start

This section describes how to use Orpie in its default configuration. After familiarizing yourself with the basic operations as outlined in this section, you may wish to consult Section 4 to see how Orpie can be configured to better fit your needs.

3.1  Overview

You can start the calculator by executing orpie. The interface has two panels. The left panel combines status information with context-sensitive help; the right panel represents the calculator's stack. (Note that the left panel will be hidden if Orpie is run in a terminal with less than 80 columns.)

In general, you perform calculations by first entering data on to the stack, then executing functions that operate on the stack data. As an example, you can hit 1<enter>2<enter>+ in order to add 1 and 2.

3.2  Entering Data

3.2.1  Entering Real Numbers

To enter a real number, just type the desired digits and hit enter. The space bar will begin entry of a scientific notation exponent. The 'n' key is used for negation. Here are some examples:

KeypressesResulting Entry
1.23<enter>1.23
1.23<space>23n<enter>1.23e-23
1.23n<space>23<enter>-1.23e23

3.2.2  Entering Complex Numbers

Orpie can represent complex numbers using either cartesian (rectangular) or polar coordinates. See Section 3.5 to see how to change the complex number display mode.

A complex number is entered by first pressing '(', then entering the real part, then pressing ',' followed by the imaginary part. Alternatively, you can press '(' followed by the magnitude, then '<' followed by the phase angle. The angle will be interpreted in degrees or radians, depending on the current setting of the angle mode (see Section 3.5). Examples:

KeypressesResulting Entry
(1.23, 4.56<enter>(1.23, 4.56)
(0.7072<45<enter>(0.500065915655126, 0.50006591...
(1.23n,4.56<space>10<enter>(-1.23, 45600000000)

3.2.3  Entering Matrices

You can enter matrices by pressing '['. The elements of the matrix may then be entered as described in the previous sections, and should be separated using ','. To start a new row of the matrix, press '[' again. On the stack, each row of the matrix is enclosed in a set of brackets; for example, the matrix

12
34

would appear on the stack as [[1, 2][3, 4]].

Examples of matrix entry:

KeypressesResulting Entry
[1,2[3,4<enter>[[1, 2][3, 4]]
[1.2<space>10,0[3n,5n<enter>[[ 12000000000, 0 ][ -3, -5 ]]
[(1,2,3,4[5,6,7,8<enter>[[ (1, 2), (3, 4) ][ (5, 6), (...

3.2.4  Entering Data With Units

Real and complex scalars and matrices can optionally be labeled with units. After typing in the numeric portion of the data, press '_' followed by a units string. The format of units strings is described in Section 3.8.

Examples of entering dimensioned data:

KeypressesResulting Entry
1.234_N*mm^2/s<enter>1.234_N*mm^2*s^-1
(2.3,5_s^-4<enter>(2.3, 5)_s^-4
[1,2[3,4_lbf*in<enter>[[ 1, 2 ][ 3, 4 ]]_lbf*in
_nm<enter>1_nm

3.2.5  Entering Exact Integers

An exact integer may be entered by pressing '#' followed by the desired digits. The base of the integer will be assumed to be the same as the current calculator base mode (see Section 3.5 to see how to set this mode). Alternatively, the desired base may be specified by pressing space and appending one of {b, o, d, h}, to represent binary, octal, decimal, or hexadecimal, respectively. On the stack, the representation of the integer will be changed to match the current base mode. Examples:

KeypressesResulting Entry
#123456<enter># 123456`d
#ffff<space>h<enter># 65535`d
#10101n<space>b<enter># -21`d

Note that exact integers may have unlimited length, and the basic arithmetic operations (addition, subtraction, multiplication, division) will be performed using exact arithmetic when both arguments are integers.

3.2.6  Entering Variable Names

A variable name may be entered by pressing '@' followed by the desired variable name string. The string may contain alphanumeric characters, dashes, and underscores. Example:

KeypressesResulting Entry
@myvar@ myvar

Orpie also supports autocompletion of variable names. The help panel displays a list of pre-existing variables that partially match the name currently being entered. You can press '<tab>' to iterate through the list of matching variables.

As a shortcut, keys <f1>-<f4> will enter the variables (“registers”) @ r01 through @ r04.

3.2.7  Entering Physical Constants

Orpie includes definitions for a number of fundamental physical constants. To enter a constant, press 'C', followed by the first few letters/digits of the constant's symbol, then hit enter. Orpie offers an autocompletion feature for physical constants, so you only need to type enough of the constant to identify it uniquely. A list of matching constants will appear in the left panel of the display, to assist you in finding the desired choice.

The following is a list of Orpie's physical constant symbols:

SymbolPhysical Constant
NAAvagadro's number
kBoltzmann constant
Vmmolar volume
Runiversal gas constant
stdTstandard temperature
stdPstandard pressure
sigmaStefan-Boltzmann constant
cspeed of light
eps0permittivity of free space
u0permeability of free space
gacceleration of gravity
GNewtonian gravitational constant
hPlanck's constant
hbarDirac's constant
eelectron charge
meelectron mass
mpproton mass
alphafine structure constant
phimagnetic flux quantum
FFaraday's constant
Rinf“infinity” Rydberg constant
a0Bohr radius
uBBohr magneton
uNnuclear magneton
lam0wavelength of a 1eV photon
f0frequency of a 1eV photon
lamcCompton wavelength
c3Wien's constant

All physical constants are defined in the Orpie run-configuration file; consult Section 4 if you wish to define your own constants or change the existing definitions.

3.2.8  Entering Data With an External Editor

Orpie can also parse input entered via an external editor. You may find this to be a convenient method for entering large matrices. Pressing 'E' will launch the external editor, and the various data types may be entered as illustrated by the examples below:

Data TypeSample Input String
exact integer#12345678`d, where the trailing letter is one of the base characters {b, o, d, h}
real number-123.45e67
complex number(1e10, 2) or (1 <90)
real matrix[[1, 2][3.1, 4.5e10]]
complex matrix[[(1, 0), 5][1e10, (2 <90)]]
variable@myvar

Real and complex numbers and matrices may have units appended; just add a units string such as “_N*m/s” immediately following the numeric portion of the expression.

Notice that the complex matrix input parser is quite flexible; real and complex matrix elements may be mixed, and cartesian and polar complex formats may be mixed as well.

Multiple stack entries may be specified in the same file, if they are separated by whitespace. For example, entering (1, 2) 1.5 into the editor will cause the complex value (1, 2) to be placed on the stack, followed by the real value 1.5.

The input parser will discard whitespace where possible, so feel free to add any form of whitespace between matrix rows, matrix elements, real and complex components, etc.

3.3  Executing Basic Function Operations

Once some data has been entered on the stack, you can apply operations to that data. For example, '+' will add the last two elements on the stack. By default, the following keys have been bound to such operations:

KeysOperations
+add last two stack elements
-subtract element 1 from element 2
*multiply last two stack elements
/divide element 2 by element 1
^raise element 2 to the power of element 1
nnegate last element
iinvert last element
ssquare root function
aabsolute value function
eexponential function
lnatural logarithm function
ccomplex conjugate function
!factorial function
%element 2 mod element 1
Sstore element 2 in (variable) element 1
;evaluate variable to obtain contents

As a shortcut, function operators will automatically enter any data that you were in the process of entering. So instead of the sequence 2<enter>2<enter>+, you could type simply 2<enter>2+ and the second number would be entered before the addition operation is applied.

As an additional shortcut, any variable names used as function arguments will be evaluated before application of the function. In other words, it is not necessary to evaluate variables before performing arithmetic operations on them.

3.4  Executing Function Abbreviations

One could bind nearly all calculator operations to specific keypresses, but this would rapidly get confusing since the PC keyboard is not labeled as nicely as a calculator keyboard is. For this reason, Orpie includes an abbreviation syntax.

To activate an abbreviation, press ''' (quote key), followed by the first few letters/digits of the abbreviation, then hit enter. Orpie offers an autocompletion feature for abbreviations, so you only need to type enough of the operation to identify it uniquely. The matching abbreviations will appear in the left panel of the display, to assist you in finding the appropriate operation.

To avoid interface conflicts, abbreviations may be entered only when the entry buffer (the bottom line of the screen) is empty.

The following functions are available as abbreviations:

AbbreviationsFunctions
invinverse function
powraise element 2 to the power of element 1
sqsquare last element
sqrtsquare root function
absabsolute value function
expexponential function
lnnatural logarithm function
10^base 10 exponential function
log10base 10 logarithm function
conjcomplex conjugate function
sinsine function
coscosine function
tantangent function
sinhhyperbolic sine function
coshhyperbolic cosine function
tanhhyperbolic tangent function
asinarcsine function
acosarccosine function
atanarctangent function
asinhinverse hyperbolic sine function
acoshinverse hyperbolic cosine function
atanhinverse hyperbolic tangent function
rereal part of complex number
imimaginary part of complex number
gammaEuler gamma function
lngammanatural log of Euler gamma function
erferror function
erfccomplementary error function
factfactorial function
gcdgreatest common divisor function
lcmleast common multiple function
binombinomial coefficient function
permpermutation function
transmatrix transpose
tracetrace of a matrix
solvelinsolve a linear system of the form Ax = b
modelement 2 mod element 1
floorfloor function
ceilceiling function
tointconvert a real number to an integer type
torealconvert an integer type to a real number
addadd last two elements
subsubtract element 1 from element 2
multmultiply last two elements
divdivide element 2 by element 1
negnegate last element
storestore element 2 in (variable) element 1
evalevaluate variable to obtain contents
purgedelete a variable
totalsum the columns of a real matrix
meancompute the sample means of the columns of a real matrix
sumsqsum the squares of the columns of a real matrix
varcompute the unbiased sample variances of the columns of a real matrix
varbiascompute the biased (population) sample variances of the columns of a real matrix
stdevcompute the unbiased sample standard deviations of the columns of a real matrix
stdevbiascompute the biased (pop.) sample standard deviations of the columns of a matrix
minfind the minima of the columns of a real matrix
maxfind the maxima of the columns of a real matrix
utpncompute the upper tail probability of a normal distribution
uconvertconvert element 2 to an equivalent expression with units matching element 1
ustandconvert to equivalent expression using SI standard base units
uvaluedrop the units of the last element

Entering abbreviations can become tedious when performing repetitive calculations. To save some keystrokes, Orpie will automatically bind recently-used operations with no prexisting binding to keys <f5>-<f12>. The current autobindings can be viewed by pressing 'h' to cycle between the various pages of the help panel.

3.5  Executing Basic Command Operations

In addition to the function operations listed in Section 3.3, a number of basic calculator commands have been bound to single keypresses:

KeysOperations
\drop last element
|clear all stack elements
<pagedown>swap last two elements
<enter>duplicate last element (when entry buffer is empty)
uundo last operation
rtoggle angle mode between degrees and radians
ptoggle complex display mode between rectangular and polar
bcycle base display mode between binary, octal, decimal, hex
hcycle through multiple help windows
vview last stack element in a fullscreen editor
Ecreate a new stack element using an external editor
Penter 3.1415…on the stack
C-Lrefresh the display
<up>begin stack browsing mode
Qquit Orpie

3.6  Executing Command Abbreviations

In addition to the function operations listed in Section 3.4, there are a large number of calculator commands that have been implemented using the abbreviation syntax:

AbbreviationsCalculator Operation
dropdrop last element
clearclear all stack elements
swapswap last two elements
dupduplicate last element
undoundo last operation
radset angle mode to radians
degset angle mode to degrees
rectset complex display mode to rectangular
polarset complex display mode to polar
binset base display mode to binary
octset base display mode to octal
decset base display mode to decimal
hexset base display mode to hexidecimal
viewview last stack element in a fullscreen editor
editcreate a new stack element using an external editor
pienter 3.1415…on the stack
randgenerate a random number between 0 and 1 (uniformly distributed)
refreshrefresh the display
aboutdisplay a nifty “About Orpie” screen
quitquit Orpie

3.7  Browsing the Stack

Orpie offers a stack browsing mode to assist in viewing and manipulating stack data. Press <up> to enter stack browsing mode; this should highlight the last stack element. You can use the up and down arrow keys to select different stack elements. The following keys are useful in stack browsing mode:

KeysOperations
qquit stack browsing mode
<left>scroll selected entry to the left
<right>scroll selected entry to the right
rcyclically “roll” stack elements downward, below the selected element (inclusive)
Rcyclically “roll” stack elements upward, below the selected element (inclusive)
vview the currently selected element in a fullscreen editor
Eedit the currently selected element with an external editor
<enter>duplicate the currently selected element

The left and right scrolling option may prove useful for viewing very lengthy stack entries, such as large matrices. The edit option provides a convenient way to correct data after it has been entered on the stack.

3.8  Units Formatting

A units string is a list of units separated by '*' to indicate multiplication and '/' to indicate division. Units may be raised to real-valued powers using the '^' character. A contrived example of a valid unit string would be "N*nm^2*kg/s/in^-3*GHz^2.34".

Orpie supports the standard SI prefix set, {y, z, a, f, p, n, u, m, c, d, da, h, k, M, G, T, P, E, Z, Y} (note the use of 'u' for micro-). These prefixes may be applied to any of the following exhaustive sets of units:

StringLength Unit
mmeter
ftfoot
ininch
ydyard
mimile
pcparsec
AUastronomical unit
Angangstrom
furlongfurlong
ptPostScript point
picaPostScript pica
nminautical mile
lyrlightyear
StringMass Unit
ggram
lbpound mass
ozounce
slugslug
lbtTroy pound
ton(USA) short ton
tonl(UK) long ton
tonmmetric ton
ctcarat
grgrain
StringTime Unit
ssecond
minminute
hrhour
dayday
yryear
HzHertz
StringTemperature Unit
KKelvin
RRankine

Note: No, Celsius and Fahrenheit will not be supported. Because these temperature units do not share a common zero point, their behavior is ill-defined under many operations.

String“Amount of Substance” Unit
molMole
StringForce Unit
NNewton
lbfpound force
dyndyne
kipkip
StringEnergy Unit
JJoule
ergerg
calcalorie
BTUbritish thermal unit
eVelectron volt
StringElectrical Unit
AAmpere
CCoulomb
Vvolt
OhmOhm
FFarad
HHenry
TTesla
GGauss
WbWeber
MxMaxwell
StringPower Unit
WWatt
hphorsepower
StringPressure Unit
PaPascal
atmatmosphere
barbar
OhmOhm
mmHgmillimeters of mercury
inHginches of mercury
StringLuminance Unit
cdcandela
lmlumen
lxlux

Note: Although the lumen is defined by 1_lm = 1_cd * sr, Orpie drops the steridian because it is a dimensionless unit and therefore is of questionable use to a calculator.

StringVolume Unit
ozflfluid ounce (US)
cupcup (US)
ptpint (US)
qtquart (US)
galgallon (US)
Lliter

All units are defined in the Orpie run-configuration file; consult Section 4 if you wish to define your own units or change the existing definitions.

4  Advanced Configuration

Orpie reads a run-configuration textfile (generally /etc/orpierc or /usr/local/etc/orpierc) to determine key and command bindings. You can create a personalized configuration file in $HOME/.orpierc, and select bindings that match your usage patterns. The recommended procedure is to “include” the orpierc file provided with Orpie (see Section 4.1.1), and add or remove settings as desired.

4.1  orpierc Syntax

You may notice that the orpierc syntax is similar to the syntax used in the configuration file for the Mutt email client (muttrc).

Within the orpierc file, strings should be enclosed in double quotes ("). A double quote character inside a string may be represented by \" . The backslash character must be represented by doubling it (\\).

4.1.1  Including Other Rcfiles

Syntax: include filename_string

This syntax can be used to include one run-configuration file within another. This command could be used to load the default orpierc file (probably found in /etc/orpierc) within your personalized rcfile, ~/.orpierc. The filename string should be enclosed in quotes.

4.1.2  Setting Configuration Variables

Syntax: set variable=value_string

Several configuration variables can be set using this syntax; check Section 4.2 to see a list. The variables are unquoted, but the values should be quoted strings.

4.1.3  Creating Key Bindings

Syntax: bind key_identifier operation

This command will bind a keypress to execute a calculator operation. The various operations, which should not be enclosed in quotes, may be found in Section 4.3. Key identifiers may be specified by strings that represent a single keypress, for example "m" (quotes included). The key may be prefixed with "\\C" or "\\M" to represent Control or Meta (Alt) modifiers, respectively; note that the backslash must be doubled. A number of special keys lack single-character representations, so the following strings may be used to represent them:

Due to differences between various terminal emulators, this key identifier syntax may not be adequate to describe every keypress. As a workaround, Orpie will also accept key identifiers in octal notation. As an example, you could use \024 (do not enclose it in quotes) to represent Ctrl-T.

Orpie includes a secondary executable, orpie-curses-keys, that prints out the key identifiers associated with keypresses. You may find it useful when customizing orpierc.

Multiple keys may be bound to the same operation, if desired.

4.1.4  Removing Key Bindings

Syntax:
unbind_function key_identifier
unbind_command key_identifier
unbind_edit key_identifier
unbind_browse key_identifier
unbind_abbrev key_identifier
unbind_variable key_identifier
unbind_integer key_identifier

These commands will remove key bindings associated with the various entry modes (functions, commands, editing operations, etc.). The key identifiers should be defined using the syntax described in the previous section.

4.1.5  Creating Key Auto-Bindings

Syntax: autobind key_identifier

In order to make repetitive calculations more pleasant, Orpie offers an automatic key binding feature. When a function or command is executed using its abbreviation, one of the keys selected by the autobind syntax will be automatically bound to that operation (unless the operation has already been bound to a key). The current set of autobindings can be viewed in the help panel by executing command_cycle_help (bound to 'h' by default).

The syntax for the key identifiers is provided in the previous section.

4.1.6  Creating Operation Abbreviations

Syntax: abbrev operation_abbreviation operation

You can use this syntax to set the abbreviations used within Orpie to represent the various functions and commands. A list of available operations may be found in Section 4.3. The operation abbreviations should be quoted strings, for example "sin" or "log".

Orpie performs autocompletion on these abbreviations, allowing you to type usually just a few letters in order to select the desired command. The order of the autocompletion matches will be the same as the order in which the abbreviations are registered by the rcfile–so you may wish to place the more commonly used operation abbreviations earlier in the list.

Multiple abbreviations may be bound to the same operation, if desired.

4.1.7  Removing Operation Abbreviations

Syntax: unabbrev operation_abbreviation

This syntax can be used to remove an operation abbreviation. The operation abbreviations should be quoted strings, as described in the previous section.

4.1.8  Creating Macros

Syntax: macro key_identifier macro_string

You can use this syntax to cause a single keypress (the key_identifier) to be interpreted as the series of keypresses listed in macro_string. The syntax for defining a keypress is the same as that defined in Section 4.1.3. The macro string should be a list of whitespace-separated keypresses, e.g. "2 <return> 2 +" (including quotes).

This macro syntax provides a way to create small programs; by way of example, the default orpierc file includes macros for the base 2 logarithm and the binary entropy function (bound to L and H, respectively), as well as “register” variable shortcuts (<f1> to <f12>).

Macros may call other macros recursively. However, take care that a macro does not call itself recursively; Orpie will not trap the infinite loop.

Note that operation abbreviations may be accessed within macros. For example, macro "A" "' a b o u t <return>" would bind A to display the “about Orpie” screen.

4.1.9  Creating Units

Syntax:
base_unit unit_symbol preferred_prefix
unit unit_symbol unit_definition

Units are defined in a two-step process:

  1. Define a set of orthogonal “base units.” All other units must be expressible in terms of these base units. The base units can be given a preferred SI prefix, which will be used whenever the units are standardized (e.g. via ustand). The unit symbols and preferred prefixes should all be quoted strings; to prefer no prefix, use the empty string ("").

    It is expected that most users will use the fundamental SI units for base units.

  2. Define all other units in terms of either base units or previously-defined units. Again, the unit symbol and unit definition should be quoted strings. The definition should take the form of a numeric value followed by a units string, e.g. "2.5_kN*m/s". See Section 3.8 for more details on the unit string format.

4.1.10  Creating Constants

Syntax: constant constant_symbol constant_definition

This syntax can be used to define a physical constant. Both the constant symbol and definition must be quoted strings. The constant definition should be a numeric constant followed by a units string e.g. "1.60217733e-19_C". All units used in the constant definition must already have been defined.

4.2  Configuration Variables

The following configuration variables may be set as described in Section 4.1.2:

4.3  Calculator Operations

Every calculator operation can be made available to the interface using the syntax described in Sections 4.1.3 and 4.1.6. The following is a list of every available operation.

4.3.1  Functions

The following operations are functions–that is, they will consume at least one argument from the stack. Orpie will generally abort the computation and provide an informative error message if a function cannot be successfully applied (for example, if you try to compute the transpose of something that is not a matrix).

For the exact integer data type, basic arithmetic operations will yield an exact integer result. Division of two exact integers will yield the quotient of the division. The more complicated functions will generally promote the integer to a real number, and as such the arithmetic will no longer be exact.

4.3.2  Commands

The following operations are referred to as commands; they differ from functions because they do not take an argument. Many calculator interface settings are implemented as commands.

4.3.3  Edit Operations

The following operations are related to editing during data entry. These commands cannot be made available as operation abbreviations, since abbreviations are not accessible while entering data. These operations should be made available as single keypresses using the bind keyword.

4.3.4  Browsing Operations

The following list of operations is available only in stack browsing mode. As abbreviations are unavailable while browsing the stack, these operations should be bound to single keypresses using the bind keyword.

4.3.5  Abbreviation Entry Operations

The following list of operations is available only while entering a function or command abbreviation, or while entering a physical constant. These operations must be bound to single keypresses using the bind keyword.

4.3.6  Variable Entry Operations

The following list of operations is available only while entering a variable name. As abbreviations are unavailable while entering variables, these operations should be bound to single keypresses using the bind keyword.

4.3.7  Integer Entry Operations

The following operation is available only while entering an integer; it can be made accessible by binding it to a single keypress using the bind keyword.

5  Licensing

Orpie is Free Software; you can redistribute it and/or modify it under the terms of the GNU General Public License (GPL), Version 2, as published by the Free Software Foundation. You should have received a copy of the GPL along with this program, in the file “COPYING”.

6  Credits

Orpie includes portions of the ocamlgsl bindings supplied by Olivier Andrieu, as well as the curses bindings from the OCaml Text Mode Kit written by Nicolas George. I would like to thank these authors for helping to make Orpie possible.

7  Contact info

Orpie author: Paul Pelzl <pelzlpj@eecs.umich.edu>
Orpie website: http://www.eecs.umich.edu/~pelzlpj/orpie

Feel free to contact me if you have bugs, feature requests, patches, etc. I would also welcome volunteers interested in packaging Orpie for various platforms.


1
The default installation prefix is /usr/local. The orpierc file will be placed in $(prefix)/etc by default; use the –sysconfdir option to choose a different location.

This document was translated from LATEX by HEVEA.