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Spacey
  • Member for 12 years, 1 month
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61 votes
3 answers
138k views

How do I exactly project a vector onto a subspace?

18 votes
2 answers
9k views

What is the intuition behind a function being 'weakly differentiable'?

9 votes
4 answers
3k views

Summary of Optimization Methods.

8 votes
1 answer
26k views

What does upside down "v" ($\wedge$) mean in this equation?

3 votes
1 answer
409 views

Why does this covariance matrix have additional symmetry along the anti-diagonals?

3 votes
3 answers
1k views

Simplify difference of two arctangents?

3 votes
4 answers
948 views

What is an example of a linear function that maps a matrix to a scalar? What makes it a 'function'?

3 votes
1 answer
1k views

Derivation of the derivative of a square matrix w.r.t. a vector

2 votes
1 answer
332 views

Why does this equation converge to 1?

2 votes
1 answer
2k views

Calculate a whitening matrix without using inverses?

2 votes
1 answer
460 views

Symmetrically make this matrix orthogonal, but don't you dare use the Frobenius norm...

2 votes
2 answers
74 views

Why does this series converge to the mean?

1 vote
1 answer
332 views

What is the geometric interpretation of a complex matrix times a real vector?

1 vote
2 answers
648 views

What is the rationale behind the evaluation of the Expectation operator?

1 vote
3 answers
5k views

Intuition behind gradient VS curvature

1 vote
1 answer
286 views

Notation question on index of the product symbol.

1 vote
1 answer
30 views

Not clear on how a simple vector subtraction was opened up to a summation.

1 vote
0 answers
25 views

Unsure how kullback-leibler was invoked in derivation.

0 votes
1 answer
40 views

Stuck on 'differentiating the integral from above' for computing of a PDF

0 votes
1 answer
117 views

Why is the norm of this matrix bounded like this?

0 votes
3 answers
251 views

What is the correct order of multiplication for this product of matricies?

0 votes
1 answer
1k views

Derivatives of vectors involving the expectation operator - Part I

0 votes
1 answer
301 views

Trying to understand the Jacobian, part I.

0 votes
1 answer
183 views

How can a function of the form $\sum \sum \frac{\lvert x_{i} - x_{j}\rvert^{p}}{p}$ be minimized? (Part I)