"Integral" is an easy to use free and open-source (LGPL v3) application to calculate mathematical integrals with many features :
- undefinite, definite and numerical integration;
- integrals in one, two and three variables (1D, 2D, 3D);
- 5 simplification methods for non-numerical results;
- three 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, 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.
"Integral" runs on Maemo 4 (Nokia N800/N810, etc), Maemo 5 (Nokia N900) or any
smartphone/tablet/computer where Python, SymPy and PyQt are available.
Future versions will use PySide and QML.
SymPy is a computer algebra system (CAS) written in pure Python, it is free and open source project, see
http://sympy.org/. SymPy last version (0.7.1, July 2011) is available for Maemo 4 (Diablo) and Maemo 5 (Fremantle), see the
SymPy thread in Talk Maemo.org.
See also the
"Integral" topic in Talk Maemo.org.
 Undefinite
integral of one variable on Nokia N900. The calculation time on is shown in green, the
non-calculated integral in blue and the result in black (with 8 zoom
levels). The Nokia N810 runs in 5.92 s.
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 Undefinite
integral of one variable using greek characters on Nokia N810. They can
be seen with the help of line completion editing of the
integrand, differentials and limits. The Nokia N900 runs in 26.60 s.
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Definite integral of 2 variables with infinity for the upper limits on Nokia N810.
The Nokia N8x0/N900 are fast enough to calculate useful integrals even
in 2 and 3 dimensions. The Nokia N900 runs in 13.23 s.
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Numerical integration in 3 dimensions that takes 591 seconds on a Nokia N900 @ 600 MHz.
It is possible to use an arbitrary number of digits, but when greater than
15 digits the numerical calculations are significantly slower. On Nokia 810 it takes 1212 s.
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The menu of "Integral" on Nokia N900 : "Zoom in", "Zoom out" and "Help"
are new features from version 1.1.0. Next versions will have "Share".
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There are many settings for "Integral", here the default ones are
shown on Nokia N900. "Symplify terms" can take a long time for large results, when it
is better to choose "None" or "Expand terms/all" as simplification
method if calculation time is important for non-numerical integration.
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Integral v1.0.0 (2011-08-11) :
-
1st public release for Maemo 5 (Fremanle) on extras-devel repository;
- uses SymPy 0.6.6 (12/2009) with 9.0 MB of Python source code;
- time to load is approx. 7 seconds on Nokia N900 @ 600 MHz.
Integral 1.1.0 ((12/09/2011) :
-
uses new version 0.7.1 (07/2011) of SymPy with 13.3 MB of Python source code, so more integrals are now solved;
-
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.
Integral 1.1.1 (14/09/2011) :
- to show greek and other symbols in bidimensional output the X Terminal is opened when starting Integral and can not be closed.
Integral 1.1.2 (15/09/2011) - current version for Maemo 5 :
- no need anymore of X terminal being opened to show greek and other symbols in bidimensional output.
Integral 1.1.3 (06/10/2011) for Maemo 4 :
- 1st release for Maemo 4 Diablo;
- using SymPy 0.7.1 (07/2011);
- time to load is approx. 20 seconds on Nokia N810.
Integral 1.1.4 (08/10/2011) for Maemo 4 :
- fix sqrt symbol for bidimensional output on Maemo 4 Diablo.
Integral 1.1.6 (23/10/2011) - current version for Maemo 4 :
- 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.
To-do list for Integral :
- starting/splash screen with useful information while "Integral" is loading;
- "Share" menu function to send the result using SMS, Email, Bluetooth, etc;
- show the source-code files of "Integral" in Git or Nokia Developer Projects, etc;
- translations in english and portuguese;
- make a QML (Qt Quick) version to run on MeeGo 1.2 Harmattan testing
it on Nokia N950 or N9, creating a "Integral.deb" for Harmattan;
- button to stop calculation;
- output with typesetting;
- run on MeeGo smartphones/tablets/netbooks, creating install file "Integral.rpm".