## the SVD: preface

Rather than edit the following SVD posts – unless I have to – let me put some prefatory material here. I am also going to answer a couple of email questions in comments, partly just to check out their mechanics.

The following posts in the math SVD category should be read in the order displayed, not starting from the back.

That may have been a bad idea on my part, but let’s see how it works out. The difficulty is that most of what I do out here will be available in the usual blog-order, latest first. Eventually it may be awkward if one category is in reverse order wrt everything else.

I would like to add two pieces of vocabulary. For the SVD $X = u\ w\ v^T$ the columns of u and v are called the left singular vectors of X and the right singular vectors of X, respectively.

I have also discovered that the latex interpreter works in comments. Cool! My understanding is that it does not work in forums; they would be the appropriate place to post code – and have it display as code! After all, that’s where I found the key starting points for latex.

### 3 Responses to “the SVD: preface”

1. rip94550 Says:

testing more of the mechanics.

i’ve seen that i posted 2 comments about the SVD in the Diary category rather than in this category. i don’t see a way to link to them.

i’ve also seen that my avatar didn’t show up. maybe i have to be logged in, as i am now?

2. blaisepascal Says:

I found the SVD stuff to be an interesting, but ultimately difficult read, precisely because I choose to read blogs in chronological order. I cannot read future postings in any other order, and I assume that past postings were at one point future postings and intended to be read in that order.

The SVD postings were an interesting challenge to that assumption.

3. rip Says:

I’m sorry it was difficult. Maybe I _ought_ to just combine 9 of the posts into 1: they were, in fact, all published on the same day.

They were my first posts (apart from “Purpose” and one chattering about latex). All my other posts have been published in the customary way.