Code covered by the BSD License

### Highlights from frontal

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# frontal

### Felipe G. Nievinski (view profile)

15 Mar 2011 (Updated )

Do: C = frontal_mtimes(A, b); not: for k=1:size(A,3), C(:,:,k) = A(:,:,k) * b(:,:,k); end

File Information
Description

These routines assist in the manipulation of matrices with same shape but different content. For example, performing the product A*b is trivial for matrix A and vector b, but what would you do if you had several such products to form? Examples abound: rotations, Jacobians, covariances, etc. Using the frontal routines, you'd collect them all in a three-dimensional matrix or third-order tensor, with each k-th frontal panel of A(:,:,k) and b(:,:,k) storing one such a related matrix and vector. Then calling

C = frontal_mtimes(A, b);

would do the equivalent of

for k=1:size(A,3), C(:,:,k) = A(:,:,k) * b(:,:,k); end

but using internally different algorithms depending on the dimensions of A (including a C-mex option). If you like operator overloading, you can do instead:

A = frontal(A);
b = frontal(b);
C = A*b;

You might want to compile the file frontal_mtimes_helper.c, but it's not required.

After you've unzipped it, test your installation running:

test_frontal

Acknowledgements
MATLAB release MATLAB 7.9 (R2009b)
16 Mar 2011 Felipe G. Nievinski

### Felipe G. Nievinski (view profile)

Don't do:

just:

as instructed.

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16 Mar 2011 James Tursa

### James Tursa (view profile)

OK. I think I have it working now, at least partially. I had to add both the frontal directory *and* the util subdirectory to the path.

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16 Mar 2011 Felipe G. Nievinski

### Felipe G. Nievinski (view profile)

Please check your unzipping procedure. I've double checked the zip and the directory structure is intact.

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16 Mar 2011 James Tursa

### James Tursa (view profile)

FYI: From the "Other Files" display above it looks like the intent is to install this as a class directory structure with some helper files. But when the zip file is downloaded there is no such directory structure. All I get is a bunch of files. So I will have to manually build the @frontal folder and then separate out the helper functions also, maybe putting them in a private directory under @frontal. Is it your intent that a person who downloads this has to build all these directory structures manually?

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