Accelerating MATLAB Performance

253Implicit Parallelization (Vectorization and Indexing)

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meshgrid

vectorized usage example

Additional examples of using meshgrid can be found in the references.

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meshgrid can

create 2D and 3D matrices; for higher dimensions, we can use ndgrid.

5.3.8 Euclidean Distances

Given two sets A,B of coordinates (x,y,z), let’s nd the Euclidean distance r from each point

in A to each point in B:

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% Common problem definition/initialization

A = rand(1000,3); % 1000 points

B = rand(3000,3); % 3000 points

sizeA = size(A,1); % # of points (rows) in A = 1000

sizeB = size(B,1); % # of points (rows) in B = 3000

% Slow, standard version ...