"Integral" is an easy to use free and open-source (GPL) application to calculate mathematical integrals with many features (depending on the version) :
* undefinite, definite and numerical integration;
* integrals in one, two and three variables (1D, 2D, 3D);
* 5 simplification methods for non-numerical results;
* 3 numerical integration methods and arbitrary number of digits (default is 15);
* option to show the calculation time;
* option to show the not calculated integral before the result;
* result with zoom levels and different colors;
* 7 output types : simple, bidimensional, typesetting (to be implemented), LaTeX, MathML, C and Fortran;
* copy&paste available in all entry fields and also in the result, allowing copying the result to anywhere;
* history and line completion editing in the integrand, differentials and limits.

See the Integral web site : http://www.robertocolistete.net/integral/.

"Integral" runs on :
- Sailfish OS with Python 3.4, SymPy 0.7.5 and Qt5/PyOtherSide (released in 19/05/2014 at OpenRepos.net);
- Maemo 4 (Nokia N800/N810, etc), Maemo 5 (Nokia N900) or any smartphone/tablet/computer where Python, SymPy and PyQt are available.

SymPy is a computer algebra system (CAS) written in pure Python, it is free and open source project. SymPy version 0.7.3 (14/07/2013) is available for Maemo 4 (Diablo) and Maemo 5 (Fremantle), and SymPy 0.7.5 for Python 2.7 and Python 3.x is available on Sailfish, see the SymPy thread in Talk Maemo.org.


Indefinite integral of one variable on Nexus 4 running Sailfish :


Indefinite integral of one variable using greek characters on Maemo 5. Timings : 38.9s on Nokia N810, 26.6s on Nokia N900, 5.54s on Nexus 4 :


A definite integral of two variables on Maemo 4. Timings : 14.9s on Nokia N810, 13.2s on Nokia N900, 3.28s on Nexus 4 :
:


A numerical integral of three variables on Maemo 5, using the default numerical integration method (optimized for infinities). Timings : 1212s on Nokia N810, 591s on Nokia N900, 121s on Nexus 4 :



Integral v0.6 (19/05/2014) released.

Integral v0.8 (23/06/2014) released.

Integral for Sailfish OS uses Python 3 and PyOtherSide, so you need Sailfish v1.0.3.8 (31/01/2014) or newer (so they are in the official Jolla repositories).

Install Warehouse (OpenRepos.net client) for Sailfish OS, see the Jolla Tides guide with screenshots.
Then open Warehouse, search for "Integral", enable the repository, then install it.

Integral takes only 0.5 MB after installation, but its dependency (which is automatically installed) "python3-sympy" (SymPy), if not installed, takes approx. 30 MB. Python 3 and PyOtherSide will also be installed if not already installed.


Version history of Integral on Maemo 4 & 5 :

(11/08/2011)
Integral v1.0.0 for Maemo 5 (Fremantle) :
* 1st public release on extras-devel repository;
* uses SymPy 0.6.6 (12/2009);
* time to load is approx. 7 seconds on Nokia N900 @ 600 MHz.

(12/09/2011)
Integral 1.1.0 :
* uses new version 0.7.1 (07/2011) of SymPy;
* bidimensional output type has correct line breaks without opening the X Terminal;
* result with zoom in and out in 8 levels;
* different colors for calculation time, non-calculated integral and result;
* 5 simplification methods instead of 3;
* Fortran output type;
* help window;
* more robust input;
* time to load is approx. 7 seconds on Nokia N900 @ 600 MHz.

(14/09/2011)
Integral 1.1.1 :
* to show greek and other symbols in bidimensional output the X Terminal is opened when starting Integral and can not be closed.

(15/09/2011)
Integral 1.1.2 is available for Maemo 5 (Fremantle) in the extrasl repository and Maemo.org Downloads :
* no need anymore of X terminal being opened to show greek and other symbols in bidimensional output.

(06/10/2011)
Integral 1.1.3 :
* 1st release for Maemo 4 Diablo.
* using SymPy 0.7.1 (07/2011);
* time to load is approx. 16 seconds on Nokia N810.

(08/10/2011)
Integral 1.1.4 :
* fix sqrt symbol for bidimensional output on Maemo 4 Diablo.

(23/10/2011)
Integral 1.1.6 is available for Maemo 4 (Diablo) in extras repository as well as Maemo.org Downloads:
* depends on python-symPy_0.7.1-maemo4 which fixes the missing dependency of python2.5-dev on Maemo 4 Diablo;
* added 'About Qt' menu item;
* 'Help' and 'About' with different dialog;
* '=' is not shown in empty output.

For the users of Integral v1.1.4 for Maemo 4, which was not running because of the missing python2.5-dev dependency, the solution is :
- uninstall "Integral"/"Derivative"/"Limit" from the application manager (it will uninstall python-sympy_0.7.1-maemo3);
- update the application manager;
- install "Integral"/"Derivative"/"Limit" so that the new python-sympy (and python2.5-dev) will be installed.

From version 1.1.3, the "About" dialog shows "In loving memory of my wife Lorena" because unfortunately she left this world in 19/09/2011.

Python, PyQt and SymPy will also be installed if not installed before.

"Integral" is small (50 KB) but it installs "SymPy", about 18.5 MB after install, with .pyc compiled Python files. Both "Integral" and "SymPy" are optified on Maemo 5.

On Maemo 4 (Diablo) "Integral" and its dependencies takes about 40 MB after install :
* SymPy (about 18.5 MB);
* python2.5-dev for SymPy, about 15 MB after install;
* "ttf-dejavu" (7,7MB after install) font because the Monospace font on Maemo 4 lacks many mathematical symbols for bidimensional output, so DejaVu Sans Mono is used.

For Maemo 5 users, please help promote Integral (v1.1.2 promoted in 01/11/2011) to extras repository by voting in :
Integral 1.1.2-fremantle2

See also "Derivative" for Maemo 4 & 5 and "Limit" for Maemo 4 & 5 & Sailfish, which calculate mathematical derivatives and limits.