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Apply ParallelMap to function f over a matrix while passing as arguments the row number and the element index

I have a matrix test = { {2.5,1.4,3.3},{4,4,4},{7,3.2,9}} and a function f that requires 2 arguments, the row number and the ...
123 views

Want advice on writing better code to do matrix calculation [closed]

I want to perform the computation shown in the code given below in a much faster way. I have three loops for e, i and ...
66 views

Optimising matrix calculation [closed]

I was calculating the elements of a matrix like this: ...
138 views

Possible to use all cores for FullSimplify-ing elements from a matrix or vector? [closed]

I understand that FullSimplify, in general, uses one core only. However, when you FullSimplify a matrix or vector, I'm guessing Mathematica simplifies each element independently of the rest, so... why ...
117 views

Running out of memory when dealing with 210 million matrix elements

I have a program for counting pixel elements in RGB with a precision of two decimal places. Each image consists of 280 x 250 pixels, and the images are stored in a folder containing 1200 images. At ...
79 views

Parallelizing code, any tips?

I have access to a Linux cluster and I'm trying to use Parallelize to run the above bellow faster, but whenever I try to place ...
175 views

Accelerating the construction of a ParallelTable

I wish to calculate a rather dense antisymmetric matrix quite fast based on a random distribution of points (and their radii) in the three dimensional space as follows: ...
85 views

How to fill in matrices by enforcing a condition on each entry quickly?

In the process of solving a 3D time-dependent PDE, I need to fill several matrices which their sizes are quite high. These matrices are constructed based on the radii of the mesh nodes in the 3 ...
269 views

Calculate the ESP Grid based on Density Grid

I want to build a fast way to convert a density grid file into a grid file of the respective electrostatic potential (ESP; also known as MEP, the molecular electrostatic potential). This calculation ...
181 views

How to speed up filling a matrix as much as possible in a loop?

In order to find the solution of an $n\times n$ system of nonlinear equations by the method $x_{k+1}=x_k-D_k^{-1}f(x_k)$ where $D_k$ is an approximation of the Jacobian and defined by \begin{equation}...
156 views

How to parallelize this code?

Initialize a matrix a with value of $\alpha$ in central cell as "ice", and $\beta$ in every other cell. ...
339 views

Parallel evaluation of symbolic matrix eigenvalues

I'm trying to find eigenvalues of symbolic hermitian 40x40 block matrix. It is made from 20 2x2 matrices like this: ArrayFlatten[Table[M[m,n],{m,1,20},{n,1,20}]] ...
164 views

Eigensystem on HPC

I am submitting Mathematica jobs to an HPC. I have a large matrix that is a function of (x,y) and I am diagonalizing it for around 500 points in the plane. My initial idea was to request a node with ...
476 views

Making Monte Carlo simulation with ParallelTable

I would like to to MonteCarlo simulations of various regressions - basically, doing OLS under various conditions to test approaches. On my macpro 2x 2.8 GHz quad core Xeon, 32 Gb RAM DDR2 @ 667 Mhz, ...
378 views

Discriminant of Characteristic Polynomial [closed]

I'm doing a calculation which finds the characteristic polynomial of a matrix with rather complex entries and then determines the discriminant of that polynomial. For smaller matrices up to around 7x7 ...
796 views

Is there a way to parallelize the convolution component of EdgeDetect?

Provided an image like - test = Import["http://upload.wikimedia.org/wikipedia/commons/d/d5/Sunflowers.jpg"] We can run ...
657 views

Is matrix multiplication automatically done in parallel in Mathematica 9?

In good old Mathematica versions (5.2, 6.0), matrix multiplication was automatically done in parallel. For example, on an 8-core machine, define two square real matrices: ...