ASCIIMath creating images

Tuesday, December 14, 2010

Adding math equations in a blogger posting

This this blog is in theory about signal processing, I had a look at how to add equations into posts, something which at first I thought to be pretty straightforward. Ok, I thought that I might have to learn MathML.  Turns out Blogger (on which this blog is hosted) uses plain html rather than htmlx (whatever that may mean) so one has to work around this problem; a quick bit of googling reveals it's a common problem, and there is a "standard" solution: ASCIIMathML.  Following the instructions here, I uploaded the script to my Google site, then added a "Gadget" (in the "Design" tab of the Blogger interface) and added the link to my copy of ASCIIMathML.js.

So does it work?

$X(\omega) = \int_{t=-\infty}^{\infty}x(t)e^{-j\omega t}dt$

Well more or appears your mileage may vary depending on what browser you are using. On Chrome the above does not quite work. Firefox does OK, reconq fails. I'll have to test Safari at home.

Still, it should be usable in most cases.

Saturday, December 11, 2010

Learning Mercurial

I have been following a pretty linear progression of revision control systems. Around 1997 (or possibly as early as 1995 in my undergraduate years) I started using RCS; I switched to CVS probably around 1999 or so. Since 2004/2005 I have been using subversion.

I'm now looking to switch to mercurial - it's what all the cool kids are using now and it appears to be then next logical step. But what will I gain from it?

I have been using subversion mostly as a versioned synchronization tool: a central repository providing me with a "ground truth" snapshot with full history. I can't find a specific use case/workflow that fits my situation: "lone developer on multiple machines", but this comes close: CVS like usage.

I'm not 100% sure I fully grasp the distributed idea yet, that every "working" dir is also a repository. I tried cloning a bundle, then pushing changes back into it - that doesn't work. But I can clone the bundle, then clone the clone, and changes can be pushed back to that! So my "svn/cvs-like workflow" is now this:

I create a repository/woking dir local on my home server.
"mkdir TestRepo; cd TestRepo; hg init"
I clone the repo remotely:
"hg clone ssh://"
Now I can edit in there and commit at my heart's content... once happy, I can push the changes back to the server.
"hg push"

And all other copies can get the updates using "hg pull".

So at least I duplicate the features of my ssh+svn setup.  Eventually, I'll learn the more advanced features of Mercurial...

Wednesday, December 8, 2010

Starting a blog

I'm really late to the party.  I decided it's time to start a blog after everyone and their dog already has one, but still, it seems easier than to constantly edit a webpage - plus this way people could comment on posts (if ever people actually read my ramblings!)

The main goal should be to keep me in the writing habit (now that my thesis is submitted).  And to blather on about whatever idea I'm currently contemplating.

Oh yeah, the title is chosen since I expect my posts to be about (digital) signal processing in some form.  Heh, I might actually try to figure out MathML to put equations into these posts...