Questo sito contribuisce alla audience di

Il tool Differentiation Matrix Suite

Ci aiuta nella differenziazione di Matrici in ambiente Matlab

E’ una suite
realizzata per Matlab 5 e costituita da 70 funzioni per la risoluzione di
equazioni differenziali con iil metodo spectral collocation.La suite è corredata
da un manuale in formato postscript (paper) che può essere scaricato in versione
compressa o meno.
Mentre la suite può essere scaricata in versione tar per le
macchine Linux,Unix, oppure in formato zip per le macchine
win9X.
Di
seguito ho riportato un elenco delle funzioni.

Sommario

Contents.m

-Differentiation Matrices (Polynomial Based)
poldif.m (General
differentiation matrices)
chebdif.m (Chebshev differentiation matrices)

herdif.m (Hermite differentiation matrices)
Requires: herroots.m,
poldif.m
lagdif.m (Laguerre differentiation matrices)
Requires:
lagroots.m, poldif.m

-Differentiation
Matrices (Non-Polynomial)
fourdif.m (Fourier
differentiation matrices)
sincdif.m (Sinc differentiation matrices)

-Boundary
Conditions
cheb2bc.m (Chebyshev 2nd derivative matrix incorporating Robin boundary
conditions)
Requires: chebdif.m
cheb4c.m (Chebyshev 4th derivative matrix
incorporating clamped boundary conditions)

-Interpolation
polint.m (Barycentric
polynomial interpolation on arbitrary distinct nodes)
chebint.m (Barycentric
polynomial interpolation on Chebyshev points)
fourint.m (Barycentric
trigonometric interpolation at equidistant nodes)

-Transform-Based
Derivatives
chebdifft.m (FFT-based Chebyshev derivative)
fourdifft.m (FFT-based
Fourier derivative)
sincdifft.m (FFT-based sinc derivative)

-Roots of
Orthogonal Polynomials
legroots.m (Roots of
Legendre polynomials)
lagroots.m (Roots of Laguerre polynomials)

herroots.m (Roots of Hermite polynomials)

-Examples
cerfa.m (Function file for computing complementary error function. BC
y(infinity) = 0.
Requires: chebdif.m, chebint.m
cerfb.m (Function file
for computing complementary error function. BC y(0) = 1
Requires: chebdif.m,
chebint.m
matplot.m (Script file for plotting characteristic curves of
Mathieu’s equation)
Requires: fourdif.m
ce0.m (Function file for
computing the Mathieu cosine elliptic function)
Requires: fourdif.m,
fourint.m
sineg.m (Script file for solving the sine-Gordon
equation)
Requires: herdif.m, herroots.m, sincdif.m, fourdif.m, poldif.m,
sgrhs.m,
sgrhs.m (Function file for computing the right-hand side of the
sine-Gordon equation)
schrod.m (Script file for computing the eigenvalues of
the Schrodinger equation)
Requires: lagdif.m, lagroots.m, poldif.m

orrsom.m (Script file for computing the eigenvalues of the Orr-Sommerfeld
equation)
Requires: cheb4c.m, chebdif.m

Per approfondire
l’argomento nonchè per scaricare la suite e la documentazione cliccare sul lik
seguente:

href="http://dip.sun.ac.za/~weideman/research/differ.html" target=_blank>A Matlab
Differentiation Matrix Suite