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Allocate null vector matlab
Allocate null vector matlab











allocate null vector matlab

Because the only thing I do here is operate on memory, I can estimate the efficiency of this code by calculating the obtained effective memory bandwidth and comparing it to the hardware memory bandwidth of my computer: eff_bandwidth = numel(x) * 8 bytes per double * 2 / time It seems to be very fast (faster at least than memory allocation). Let's call it method 1 (from the value assigned to x). The simplest way is to write: tic x(:) = 1 toc

allocate null vector matlab

In practice you would do it differently, e.g., x = value*ones(1e8,1), but the point here is to investigate the performance of vector indexing. Having x I would like to set all its entries to the same value. First, I allocate an empty vector x: tic x = zeros(1e8,1) toc The example codes shown below are as fundamental as it gets: I assign a scalar value to all vector entries. Investigating performance of vector indexing The bottom line: core MATLAB functionality is efficient and trying to outperform it using MATLAB code is hard, if not impossible.

  • Loops in MATLAB are slow (despite the JIT) and should generally be avoided if the algorithm can be expressed in a native, 'vectorized' manner.
  • MATLAB is very well optimized when it comes to the built-in functions and the fundamental language features, such as indexing vectors and matrices.
  • allocate null vector matlab

    My question is motivated by simple observations, which somewhat undermine the beliefs/assumptions often held/made by experienced MATLAB users:













    Allocate null vector matlab