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seen Feb 21 at 4:53

Jul
2
awarded  Curious
Oct
27
comment How to calculate gradient of $x^TAx$
I have some difficulties in understanding the derivations below the row ends with "+ small term" in the equation array, could you give me some hints? Thank you!
Oct
27
accepted Questions on “painless conjugate gradient”: take gradient of a quadratic form
Oct
27
comment Questions on “painless conjugate gradient”: take gradient of a quadratic form
I really like this flavor of derivation, it is more straightforward and avoids the problems I encountered. Please review the minor fix on one equation in your answer. Thank you. @littleO Thank you very much for other solutions. I am interested in your answer in that Q/A(which seems to solve my first sub-question). I leave a comment in your answer for some details.
Oct
27
revised Questions on “painless conjugate gradient”: take gradient of a quadratic form
Add the missing 1/2 factor to the third term in the right hand side of the equation in the "As a result" paragraph.
Oct
27
suggested suggested edit on Questions on “painless conjugate gradient”: take gradient of a quadratic form
Oct
27
asked Questions on “painless conjugate gradient”: take gradient of a quadratic form
Oct
14
accepted Confusion about Monte Carlo integration
Sep
26
asked Confusion about Monte Carlo integration
May
24
comment Why can I integrate something like “infinitesimal part” to calculate the length, area, volume, etc.?
em....it seems that I did not state my question clearly. Yes, I understand I need to choose different integrand based on different definition of "distance". But further I want to know why a particular integrand(is that so called measure?) can be integrated to get correct length/area/volume. In low dimensions(<=3) and with real life appreciable measure(length/area/volume), the intuition can help me to determine the correct integrand. But in higher dimension or with an "artificial" measure(like probability) I find it very difficult.
May
23
asked Why can I integrate something like “infinitesimal part” to calculate the length, area, volume, etc.?
Feb
24
asked The mathematics behind Sobol sequences
Nov
19
asked Re-calculate solution after altering some elements in a linear system
Oct
19
asked uncertainty in solving constraint problem
Oct
14
asked Is it possible to change a piece of curve's interpolation type of a B-Spline via modifying knots?
Sep
21
awarded  Custodian
Aug
28
accepted Problem in Deducing Perspective Projection Matrix
Aug
24
revised Problem in Deducing Perspective Projection Matrix
added 501 characters in body
Aug
23
awarded  Supporter
Aug
23
accepted what's the general form of 3D projective mapping?