Matrix approach to distributed-order ODEs and PDEs

Basic functions for using matrix approach for distributed-order differential equations, and demos.

This submission contains the basic functions that are necessary for using the matrix approach to discretization of distributed-order differential equations, and demos.

It provides the Matlab code from Appendices 4-6 to the following book:
[1] Zh. Jiao, YQ. Chen, I. Podlubny: "Distributed-Order Dynamic Systems: Stability, Simulation, Applications and Perspectives", Springer, London, 2012, ISBN 978-1-4471-2851-9, (http://www.springer.com/engineering/control/book/978-1-4471-2851-9).

The code from Appendices 1-3 can be found in FEX submission #36574 "Demos for investigating distributed-order linear time-invariant systems" by Zhuang Jiao (http://www.mathworks.com/matlabcentral/fileexchange/36574).

The matrix approach for differential equations with fractional-order derivatives in the case of constant orders of derivatives is described in the following articles:
[2] I. Podlubny, "Matrix approach to discrete fractional calculus", Fractional Calculus and Applied Analysis, vol. 3, no. 4, 2000, pp. 359-386 (http://people.tuke.sk/igor.podlubny/pspdf/ma2dfc.pdf ).
[3] I. Podlubny, A. Chechkin, T. Skovranek, YQ. Chen, B. M. Vinagre Jara, "Matrix approach to discrete fractional calculus II: partial fractional differential equations", Journal of Computational Physics, vol. 228, no. 8, 1 May 2009, pp. 3137-3153, http://dx.doi.org/10.1016/j.jcp.2009.01.014 (preprint: http://arxiv.org/abs/0811.1355 )

For more information about fractional differential equations (i.e., differential equations containing derivatives of arbitrary real order) see, for example,
[4] I. Podlubny, Fractional Differential Equations, Academic Press, San Diego, 1999, ISBN 0125588402.