Now we start to think about transformations between dimensions, e.g. taking a 2D vector into a 3D space. Non-square matrices come up frequently in engineering and research applications, including fMRI analysis, so you'll want a good understanding of their meaning.
A8. Non-square matrices
Let's look at a simple physical interpretation of changing the number of dimensions.
We previously saw how to invert a square matrix. But how do we invert a non-square matrix?
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