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Welcome to my blog, which was once a mailing list of the same name and is still generated by mail. Please reply via the "comment" links.

Always interested in offers/projects/new ideas. Eclectic experience in fields like: numerical computing; Python web; Java enterprise; functional languages; GPGPU; SQL databases; etc. Based in Santiago, Chile; telecommute worldwide. CV; email.

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Beagle, Computing in Science and Engineering

From: "andrew cooke" <andrew@...>

Date: Wed, 24 Dec 2008 11:05:23 -0300 (CLST)

While at the AGU conference I noticed this magazine (Computing in Science
and Engineering) -

It's not the most professional looking magazine in the world, but it is by
far the closest I've found to a magazine that covers the kind of work I
do.  So I subscribed - got a cheap price and the last 10 years on CD.

I copied the back issues from CD to my hard drive and then wondered what
to do.  They are broken down into one article per file, but they are PDF
and I had no way of searching them.

Then I remembered Beagle, which I have carefully de-installed from my
computer for several years now because it seemed (1) useless and (2) used
up so much CPU.  Beagle is the default Linux document indexing system
(think Google for your local disk).

Anyway, it's improved hugely.  It no longer locks up the computer when
you're trying to get something done.  And it appears to return moderately
useful results.  So I can now search for something like "python numerical
vector" and the second hit (when ordered by relevance) is "Python for
Scientific Computing" from the magazine.

You can also restrict to certain file types (ext:pdf), exclude terms
(-foo), etc etc.  It even indexes music metadata (so you can search for
artists) and email.

The KDE Kerry interface does quite a good job of presenting the data too -
you can click on a file and it is handed off to an appropriate handler
(although HTML is going to konquerer instead of the mozilla configured for
the desktop).

It does, however, still seem to crash quite regularly.  You can see this
by doing

  tail ~/.beagle/Log/current-Beagle

which will show a message about SIGSEGV or by typing beagle-status which
will say it cannot connect.  To restart just type "beagled" at the command

I also enabled extended filesystem attributes by modifying the fstab from
/home to include the user_xattr option.  Apparently this makes things a
bit faster.

One check I did, when I found some old files I thought I had been deleted,
surprised me: it immediately picks up on deleted files and excludes them
from the results.  Which is nice.


Tweaking Beagle and KDE

From: "andrew cooke" <andrew@...>

Date: Wed, 31 Dec 2008 12:32:28 -0300 (CLST)

While Kerry (the KDE Beagle client) looks nicer (more compact), it hangs
regularly.  The Beagle search app (beagle-search from the command line, or
just "Search" from the SuSE menu) is much more robust.

If you use Firefox, you need to make sure that:

1 - the default browser is Firefox.  Configure Desktop -> General ->
Default Applications -> Web Browser

2 - html files are associated with Firefox.  Configure Desktop -> Advanced
-> File Associations and then find text/html in the tree widget.

To make sure that everything is indexed at the start, follow the
instructions at

 $ beagle-shutdown
 $ beagled

Also enable user attributes on your file system by modifying /etc/fstab as
described at

To check what is happening, use beagle-status, but don't be worried if
there are a lot of directories to scan on subsequent logins.  Each login,
beagle slowly re-scans everything.

To check whether a particular file is indexed, use
  beagle-query uri:file:///path/to/file
and see fi anything is returned.

I still haven't worked out how to get email indexed.  I use imap, and have
the files downloaded locally, but I don't use kmail or evolution and the
files are generally in directories whose names begin with a "dot".  I
think you can fake things by configuring kmail or evolution (in addition
to the email client you actually use), but this still doesn't track any
changes.  The file backend will handle emails, but doesn't look in "dot"
files.  Apparently symlinks don't fool it either...


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