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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 ...
1answer
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 ...
1answer
66 views

### Optimising matrix calculation [closed]

I was calculating the elements of a matrix like this: ...
0answers
120 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 ...
1answer
116 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 ...
0answers
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 ...
2answers
173 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: ...
1answer
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 ...
1answer
268 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 ...
1answer
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}...
2answers
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. ...
0answers
334 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}]] ...
1answer
163 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 ...
1answer
474 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, ...
0answers
368 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 ...
1answer
650 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: ...
1answer
477 views

### Parallelize matrix operations

I'm trying to reduce to a minimum the time of some matrix operations. When I don't parallelize and write the code in the most compact form I get the operation done in around 1sec (is this good? the ...
2answers
781 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 ...
1answer
2k views

### Nesting Parallel processes

I just attempted to run code that had nested ParallelMap[] functions. It generates the error message: ParallelMap::subpar: Parallel computations cannot be nested; proceeding with sequential ...