"Derivative" is an easy to use free and open-source (LGPL v3) application to calculate mathematical derivatives with many features :
"Derivative" runs on Maemo 4 (Nokia N800/N810), 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 SymPy last version (0.7.1, July 2011) is available for Maemo 4 (Diablo) and Maemo 5 (Fremantle), see the SymPy thread in Talk

  Derivative for Maemo 4 & 5
See also the "Derivative" topic in Talk

Second derivative of square root with respect of x
Second derivative of square root with respect of x, on Nokia N810. "Symplify all" setting is responsible for the long calculation time and the short result. On Nokia N900 it takes 39.5 s.
Multiple and partial derivative
On Nokia N900, multiple and partial derivative of a wave function of 2 variables, x and t, using greek characters.
Gradient of eletric potential
Gradient operator on Nokia N810 of a (negative) eletric potential yielding the eletric vector field in spherical coordinates.
Divergence of eletric field
Divergence operator on Nokia N900 of a eletric vector field in spherical coordinate system, with the result given in terms of Dirac delta function.
Curl of a generic function
Curl of a generic function in cartesian coordinate system on Nokia N900.
Example of aplacian operator
First terms of the laplacian operator of a generic function in spherical coordinate system on Nokia N900.
Menu of Derivative
Menu of "Derivative" on Nokia N900 shows that the vector differential operators (grad, div, curl and laplacian) are also available.
Settings for Derivative
The default settings of "Derivative" on Nokia N900. Simplification methods "Symplify terms" /"Symplify all" can take a long time for large results, so the default is "None".

Derivative v1.0.0 (16/10/2011) :
Derivative v1.0.2 (22/10/2011) for Maemo 4 Diablo :
To-do list for v1.1 onwards :

Download, Install & Run

See also Integral and Limit, very easy to use softwares to calculate mathematical integrals and limits.

Following softwares, all free and open-source, using Python&SymPy and Qt :

Author : Roberto Colistete Júnior (replace the " arroba " by "@")

Last updates : 06/11 (v1.1.2 for Maemo 5 is in extras), 23/10 (v1.0.2), 17/10 (v1.0), 08/08 (v0.9 with grad, div, curl and laplacian), 05/08/2011. - free web hosting. Free hosting with no banners.
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