# The &cantor; Handbook

## Introduction

&cantor; is an application to allow you to you use your favorite mathematical applications from within an elegant &kde;-integrated Worksheet Interface. It provides dialogs to assist with common tasks and allows you to share your worksheets with others.

## Using &cantor;

Screenshot: Here is a screenshot of &cantor; Screenshot

### &cantor; features

- Intuitive worksheet view for evaluating expressions.

- Results of graph plotting shown inside the worksheet.

- Easy plugin-based structure to allow different backends to be added.

- GetHotNewStuff integration to allow example worksheets to be downloaded (or uploaded.)

- Mathematical formula typesetting using LaTeX.

- Backend-aware syntax highlighting.

- Plugin-based assistant dialogs to help with common tasks, such as integrating a function, or entering a matrix.

### The &cantor; backends

&cantor; offers you several choices for the backends you wish to use with it. The choice to make depends on what you want to achieve.

Currently the following backends are available:

Sage:

- Sage is a free open-source mathematics software system licensed under the GPL. It combines the power of many existing open-source packages, within a common Python-based interface. See http://sagemath.org for more information.

Maxima:

- Maxima is a system for the manipulation of symbolic and numeric expressions, including differentiation, integration, Taylor series, Laplace transforms, ordinary differential equations, systems of linear equations, polynomials, sets, lists, vectors, matrices, and tensors. Maxima yields high-precision numeric results by using exact fractions, arbitrary precision integers, and variable precision floating point numbers. Maxima can plot functions and data in two and three dimensions. See http://maxima.sourceforge.net for more information.

R:

- R is a language and environment for statistical computing and graphics, similar to the S language and environment. It provides a wide variety of statistical (linear and nonlinear modelling, classical statistical tests, time-series analysis, classification, clustering, ...) and graphical techniques, and is highly extensible. The S language is often the vehicle of choice for research in statistical methodology, and R provides an open-source route to this. See http://www.r-project.org for more information.

KAlgebra:

- KAlgebra is a MathML-based graph calculator, that ships with KDE Education project. See http://edu.kde.org/kalgebra/ for more information.

Qalculate!:

- Qalculate! is not your regular software replication of the cheapest available calculator. Qalculate! aims to make full use of the superior interface, power and flexibility of modern computers. The center of attention in Qalculate! is the expression entry. Instead of entering each number in a mathematical expression separately, you can directly write the whole expression and later modify it. The interpretation of expressions is flexible and fault tolerant, and if you nevertheless do something wrong, Qalculate! will tell you so. Not fully solvable expressions are however not errors. Qalculate! will simplify as far as it can and answer with an expression. In addition to numbers and arithmetic operators, an expression may contain any combination of variables, units, and functions. See http://qalculate.sourceforge.net/ for more information.

Scilab:

- Scilab is an free software, cross-platform numerical computational package and a high-level, numerically oriented programming language.

  Scilab is distributed under CeCILL license (GPL compatible). See http://www.scilab.org/ for more information.

  You need Scilab version 5.4 or higher to be installed in your system to make this backend usable.

  Scilab version of the master branch of the Scilab's repository is compatible.

### The &cantor; Workspace

Screenshot of the &cantor; Workspace Screenshot of the &cantor; Workspace

The Worksheet interface of &cantor; consists of three parts:

1. The tab bar, where you can switch through the open worksheets;

2. A help panel, where help for a specific command is displayed if you enter "? command";

3. The worksheet itself.

#### The Worksheet

The worksheet is the basic area for working with &cantor;. Using it, you can enter expressions, allow the backend to perform calculations, and look at the results. The commands the worksheets accept depend on the chosen backend, so you should learn the appropriate backend syntax (the Show Help button takes you there directly). If you know the command, but you need additional information, you can type "? command", and contextual help will appear on the right of the worksheet. If you want to see some example worksheets, you can go to Download Example Worksheets in the File menu, and download worksheets other users have published.

##### Settings

The Settings menu allows you to change some settings of the appearance of your current worksheet.

Typesetting using LaTeX

- This setting changes the way results are presented to you. If enabled, it passes the result through the LaTeX system, to produce visually appealing formulas. For example, 3*x^2*sqrt(2)*x+2/3 becomes 3*x^2*sqrt(2)*x+2/3

Syntax Highlighting

- Syntax Highlighting increases the readability of code, by highlighting keywords, or matching brackets in different colors.

Completion

- When this is enabled, &cantor; will show you possible completions for the command you are currently typing when you press the Tab-key. If there is only one choice remaining, it will insert the rest of the command for you.

Line Numbers

- This setting controls whether the different expressions should have a number in front. This allows you to recall older results - in Maxima, for instance, this is done with the %O1 command.

## Command Reference

### The main &cantor; window

#### The File Menu

&Ctrl;N File New

- Creates a new worksheet with the default backend.

File New `Backend`

- Creates a new worksheet with the chosen backend.

&Ctrl;O File Open

- Opens the chosen worksheet that was saved earlier.

File Download Example Worksheets

- Opens the dialog to download examples uploaded by other &cantor; users with GetHotNewStuff.

File Open Example

- Opens the dialog to choose an example to load. The examples should be downloaded with File Download Example Worksheets beforehand.

&Ctrl;S File Save

- Saves the current worksheet.

File Save As...

- Allows saving the current worksheet with a new name.

File Export to LaTeX

- Allows saving the current worksheet as a LaTeX document.

File Publish Worksheet

- Opens the dialog to publish your current worksheet and make it available to other &cantor; users through GetHotNewStuff.

&Ctrl;P File Print

- Opens the printing dialog for the current worksheet.

File Run Script

- Allows to load and run the batch scripts for the current backend.

&Ctrl;W File Close

- Closes the current worksheet.

&Ctrl;Q File Quit

- Quits &cantor;

#### The View Menu

&Ctrl;+ View Zoom In

- Zoom in the current worksheet by 10%.

&Ctrl;- View Zoom Out

- Zoom out the current worksheet by 10%.

View Show Script Editor

- Opens the batch script editor window for the current backend.

View Panels Help

- Toggles the visibility of the Help sidebar.

#### The Worksheet Menu

Worksheet Evaluate Worksheet

- Triggers the evaluation of the whole worksheet.

&Shift;Return Worksheet Evaluate Entry

- Triggers the current entry evaluation.

&Ctrl;Return Worksheet Insert Command Entry

- Inserts a new command entry below the current cursor position.

Worksheet Insert Text Entry

- Inserts a new text entry below the current cursor position.

Worksheet Insert Image

- Inserts the image template below the current cursor position. You will need to click with &RMB; at the template to configure the image details.

Worksheet Insert Page Break

- Inserts the page break below the current cursor position.

&Shift;Del Worksheet Remove current Entry

- Removes current entry from the worksheet.

#### The Settings Menu

This menu contains standard &kde; Settings items, as well as the items described in Settings section.

#### The Help Menu

&help.menu.documentation;

## Developer's Guide to &cantor;

&cantor; is easily extendable by plugins. You can write

Backends:

- A new backend enables you to use the &cantor; interface with a different program.

Assistants:

- Assistants provide dialogs to allow common tasks to be automated (such entering a matrix or running a script.)

At present, there are no special developer tutorials or API documentation, so if you want to write a plugin you will have to read through the sources. All interface definitions are in the lib directory. For some example implementations, look at the plugins shipped with &cantor;.

## Questions and Answers

&reporting.bugs; &updating.documentation;

The Menu Item Typeset using LaTeX is not available

Not every Backend supports every option.

I have installed Sage/Maxima, but the appropriate backend does not appear.

One possible explanation is that &cantor; did not correctly detect the location. Go to the Settings dialog and change the Path to the appropriate application.

What a peculiar name - what does it have to do with mathematics?

Cantor is named after the German mathematician Georg Cantor, the creator of set theory.

## Credits and License

&cantor;

Program copyright 2009-2011 Alexander Rieder alexanderrieder@gmail.com

Documentation Copyright © 2009-2011 Alexander Rieder alexanderrieder@gmail.com

&underFDL; &underGPL;

## Installation

### How to obtain &cantor;

&install.intro.documentation;

### Requirements

In order to successfully use &cantor;, you need &kde; 4. If you want support for type-setting to be enabled, you need to install LaTeX and LibSpectre. To use the different Backends, the appropriate math package is required.

### Compilation and Installation

&install.compile.documentation;

### Configuration

Depending on your system, you may need to adjust the paths to the different applications used by &cantor;.

&documentation.index;