Octave is a (mostly Matlab® compatible) high-level language, primarily intended for numerical computations. It provides a convenient command-line interface for solving linear and nonlinear problems numerically.
Octave uses some of the best and most respected numerical libraries as balgen, dassl, eispack, fftpack, lapack, linpack, minpack, odepack, ranlib, slatec-fn and villad. Octave can be dynamically extended with user-supplied C++ files.
More information on the project web site. It's got a long list of package dependencies, but for the Matlab® fans in the crowd, it could be what you're looking for.
More information on this package can be found on the Debian web site.
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