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Determining the indices of a VTK mesh

I am trying to assign fixed constraint at specific indices of VTK mesh, however, I only can view STL file in a blender as follows: Upon assigning the favored indices in my scene at the SOFA physics ...
53 views

43 views

Maximum and Minimum distance from query point within bounding box

I'm reading an article regarding approximating sums using KD-trees (similar to FMM). As part of the effort I'm trying to make sense of this article , which is cited. I'm having trouble understanding ...
43 views

Differences between Discrete Fourier Transform and Continuous Fourier Transform?

I am trying to visualize the time dependence of a free particle given an initial wave-function using Python and I just wanted to know if I could use the in built FFT implementation from NumPy to find ...
43 views

what algorithm do BLAS and ATLAS use for matrix multiplication

I have searched and what I understood was that they use the naive one with several memory and cache optimization but I wanted to know are they using strassen or copper smith algorithms and if they ...
81 views

Lapack symmetric update $B^{-1}AB^{-T}$

Does Lapack have a routine that, given symmetric $A=A^T$ and $B$, computes the symmetric matrix $B^{-1}AB^{-T}$ (while preserving symmetry exactly)? It would be enough to have this routine for ...
2k views

What is the difference between MATLAB and FORTRAN?

In our university some Ph.D students for computational methods prefer FORTRAN over MATLAB. I can't understand why? What is the difference between them when are used in computational methods like ...
7k views

Linear interpolation in Fortran

Is there a Fortran subroutine which performs linear interpolation in one-dimenional data? I need something similar to MATLAB function interp1.
392 views

Assembling sparse matrix in PETSC for Poisson equation

I am a novice at PETSC, and I have been trying to write an FVM code for steady heat conduction in 2D using PETSC (square, regular grid, Dirichlet boundaries) Since the large matrix , say A, will be ...
84 views

Parallelizing Newton-method in solving non-linear systems

Circuit simulation software based on SPICE (such as ngspice) uses Newton-Raphson method to solve non-linear system of equations ...
37 views

Access PETSc data in totalview?

Is it possible to view the data stored in the various PETSc data types from within totalview? Ordinarily, PETSc types are integers which act as pointers to the actual data (obviously my understanding ...
69 views

Fenics: solving the same PDE multiple times

I am new to Fenics and just started reading the tutorial Solving PDEs in Python. For simplicity, we can refer to simplest example, page 17 (the linear poisson equation), despite not necessary. My ...
55 views

Vectorization of Jacobi iteration

Assume I have a linear system of $A x = b$ which I want to solve with Jacobi iteration. Matrix $A$ is given in CSR format. The vectors are dense. The code for Jacobi iteration is quite clear and can ...
57 views

Eigenfaces Algorithm

This might be a silly quesntion but recently I've been trying to program the eigenface algorithm using PCA, so I arranged the face vectors vertically in a matrix X such as: X = [x1,x2,x3,...,xn]; In ...
112 views

GPGPU computing, software selection

I am using an existing GCC C++ x86 Qt application that filters, displays and stores results computed by some C code. Since the computation by now got too complex for CPUs I intend to port the small C ...
99 views

Is using std::valarray considered good practice?

C++ has had the std::valarray class since the C++98 standard. It is meant to facilitate numerical computations, providing the sort of operations one would expect of ...
Suppose $A,B\succeq0$ and $C\in\mathbb R^{n\times n}$. I am hoping to solve an instance of the following optimization problem:  \min_{\textrm{permutation matrices }P} \mathrm{tr}(BP^\top AP+C^\top ...