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### How to Run MPI-3.0 in shared memory mode like OpenMP

I am parallelizing code to numerically solve a 5 Dimensional population balance model. Currently I have a very good MPICH2 parallelized code in FORTRAN but as we increase parameter values the arrays ...
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### Comparing Jacobi and Gauss-Seidel methods for nonlinear iterations

It is well known that for certain linear systems Jacobi and Gauss-Seidel iterative methods have the same convergence behavior, e.g. Stein-Rosenberg Theorem. I am wondering if similar results exist for ...
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### For noisy or fine-structured data, are there better quadratures than the midpoint rule?

Only the first two sections of this long question are essential. The others are just for illustration. Background Advanced quadratures such as higher-degree composite Newton–Cotes, Gauß–Legendre, ...
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I'm dealing with a coupled system of three transient, non-linear convection-diffusion equations. Let's just say to simplify the problem that they take the following form: $$-\nabla\cdot(D_{1}(u_{2},... 0answers 304 views ### Operator Splitting methods for DAEs After doing some research, I've found that most of the literature on operator splitting methods (e.g. Strang Splitting, Fractional Step, etc.) are specifically designed for a standard problem type of ... 1answer 284 views ### DG local equation, how to interpret mean-averaged test function In the paper http://www.sciencedirect.com/science/article/pii/S0045782509003521, an HDG element-local equation is described on page 584 equation (4), with one of the equations taking the following ... 0answers 403 views ### Fast Eigenvalue and SVD Solver for Structured Matrices I am looking for a fast Eigenvalue and SVD solver for small dense structured matrices (Hankel and Toeplitz). I have searched for efficient implementations in libraries like MKL but I am not able to ... 0answers 98 views ### Are there shortcuts for numerically approximating systems of ordinary differential equations when autonomous? Existing algorithms for solving ODEs handle functions \frac{dy}{dt} = f(y, t), where y \in \mathbb R^n. But in many physical systems, the differential equation is autonomous, so \frac{dy}{dt} = f(... 0answers 126 views ### Inverse problem in linear ODE I have a linear ordinary differential equation (ODE) with a system matrix with constant coefficients:$$\dot{y}(t) = \mathcal{A}\; y(t), \quad y(0) = y_0$$with y(t) \in \mathbb{R}^{n \times 1} and ... 0answers 2k views ### Alternatives to hdf5 I've been using HDF5 for years, but as the size of the dataset grows I'm starting to experience the same problems listed here http://cyrille.rossant.net/moving-away-hdf5/ Can you point me to a ... 0answers 107 views ### Are there any standardized file formats for point group character tables? Character tables are an important tool for symmetry analysis in many computational chemistry software packages. Are there any standardized file formats for point group character tables? This may seem ... 0answers 369 views ### Numerical implementation of the Dirichlet-to-Neumann map I am solving the Dirichlet problem$$ \begin{cases} \Delta u = 0, \\ u|_{\partial D} = f, \end{cases} $$in a 2d domain D using the finite element method. What I want to get is the ... 1answer 441 views ### Time discretization of the variational formulation of the Navier-Stokes equation I've asked this question on mathoverflow too. Let T>0 I:=(0,T] d\in\mathbb N \Lambda\subseteq\mathbb R^d be nonempty and open,$$\mathcal V:=\left\{\phi\in C_c^\infty(\Lambda,\mathbb R^d):...
Problem statement I implemented geometric multigrid for $-\nabla^{2}=f$ where $f=\frac{3\pi^{2}}{4}sin \frac{\pi x}{2} sin \frac{\pi y}{2} sin \frac{\pi z}{2}$ on $\Omega \in [0,1]$ on a unit cube. ...