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notthingnill

Re:MathML in Chromium on Saturday March 09, 2019 @04:50AM (#19345383)
You can also use a computer algebra system (CAS) to perform computations and get the output in mathml, for example the free CAS maxima.

wxMaxima is something like jupyter notebook but developed with wxWindows by a solo developer. ?? is help for command

I just copy pasted:

(%i2) ?? mathml; -- Function: mathml_display (<form>) Produces MathML output. (%i1) load("alt-display.mac")$ (%i2) set_alt_display(2,mathml_display); <math xmlns="http://www.w3.org/1998/Math/MathML"> <mi>mlabel</mi> <mfenced separators=""><msub><mi>%o</mi> <mn>2</mn></msub> <mo>,</mo><mi>done</mi> </mfenced> </math> (%o2) true

I wonder if some variation of this experiment would be useful for retina detachment, personal interest (my retina was completely detached and I was left with 0.60 vision in the left eye).

What's the effect of giving more information to the cells, would the brain use the extra information to self improve vision? In my case the right eye would be used for training the left one.

Another experiment I am thinking of, If a 3 month old child suffer a retina detachment, would his brain be able to recover the full vision by the brain making appropriate changes?

Re:Immersive Linear Algebra (2016) on Thursday February 28, 2019 @06:09PM (#19276298)
A lot of work for a null reward. So not really.
"The big idea is taking local data and seeing if it patches together."

I wonder if those new techniques are different from the usually used like: weighted averages of random forest, cross entropy of density estimation, minimization of variance between local estimations and the like.

Five minutes reading https://johnhw.github.io/umap_primes/index.md.html

Without using any category, topology of sheaf theory, this is what I believe is in this paper:

(1) the prior hypothesis is that data points in R^n are a sample from a uniform distribution in a Riemann space.

(2) Try to define a Riemann metric such that the number of sample points in any ball B is propotional to the volume of B.

(3) Since (2) doesn't define a global Riemann metric, they define a fuzzy membership relation. I suppose the role of the fuzzy tool is that local distance information is weighted according to the variance of the local distance estimations.

Disclaimer, I could be completely wrong.

Re:Hacker News Meetups on Wednesday February 27, 2019 @05:06PM (#19267385)
I would be disappointed to discover that the collective intelligence that I find in HN is not well represented when I speak with any member of the HN community, so better to continue with my bliss ignorance.
Re:Immersive Linear Algebra (2016) on Wednesday February 27, 2019 @04:00PM (#19266882)
I think your idea can be developed today by selecting online forums centered on topics. The main problem is moderation and how to plan the journey.
Re:Immersive Linear Algebra (2016) on Wednesday February 27, 2019 @03:49PM (#19266796)
Thank you for your free book. Another great book is Gilbert Strang's book: Introduction to Linear Algebra. Also Boyle: Linear Algebra and its Applications.

Perhaps your free book can be used to develop some evolving tool for the student. For example: the student take a test and then the book select the best exercises and topics for that student.

Re:Immersive Linear Algebra (2016) on Wednesday February 27, 2019 @03:26PM (#19266620)
Apart from Gauss elimination, I think eigenvalues, eigenvectors, scalar product, orthogonal subspaces, and the relation to statistics are important. Statistics associated with SVD, principal components and other topics are a main source of insights. Also Fourier basis is an important concept far beyond Gauss elimination.
Re:Jeff Bezos at YC Startup School 2008 [video] on Tuesday February 19, 2019 @03:21PM (#19202409)
In Messy: How to Be Creative and Resilient in a Tidy-Minded World, Tim Harford describe the strategy of the initial period of Amazon, and compare Bezos with Erwin Rommel, the desert Fox.