Fighting with computers

I do love Inkscape program. However, there is one thing it is still missing (it's not the program's fault though), the ability to handle more than one page documents. I recently was producing some drawings at work and I wanted to make a single document package with all the drawings to be emailed to my colleagues. As I can produce PDF output from Inkscape, I searched for easy ways to merge several PDF files. I do know Adobe's Acrobat can do that , but I was looking for a cheaper alternative. I learned that you can use command-line ghostscript to get this done (provided you have it installed) easily. gs -sPAPERSIZE=a4 -dNOPAUSE -dBATCH -sDEVICE=pdfwrite -sOutputFile=outfile.pdf inputfile1.pdf ... inputfileN.pdf I learned too that it can be done online, in fact there are several sites ( mergepdf , joinpdf ) you can use. Though there are certain limitations (encrypted PDF files are a no go), it seems I no longer have to worry about creating multipage PDF easily (of course it w...

One of the cool features about some VMware products is that they are free. Both VMware Server and ESXi are free virtualization platforms. The main difference is that while VMware server is running on top of your computer operating system, ESXi is a thin software layer running over your hardware. That saves important resources that can be better used by the virtual machines you want to run on top. ESXi only uses 32MB of RAM. You can watch this presentation about ESXi. The main problem I've got at the moment to get ESXi tested is that I need to buy a SATA disk as PATA is not supported.

I've just read today on Amazon.com website a Jeff Bezos letter announcing the availability of Kindle for customers outside U.S . Of course this also means that wireless access is going to work in your country. I'd be buying one now if DX was available. Unfortunately only 6" Kindle is offered at the moment. However I guess they will be adding DX soon. Update: There are a few things that do not add up well. Kindles are only sold from U.S. at the moment. That means you have to pay customs, plus overseas shipping plus an slightly more expensive version of Kindle. Another source of trouble is that Wireless acccess to Wikipedia from Kindle International has "experimental" status, whatever that means. It is not so with US Kindle. And to me, wireless free access to Wikipedia is well worth a price premium. But ... if Wikipedia access is dropped then I do not see enough value on the wireless delivery of paid content.

There are many ways to measure the "output" of a researcher. It is likely there are many ways to measure it because none of them is right for all the cases. While many consider citations of a paper as some type of endorsement of other person's work, there many ways to turn that into numbers. And we want numbers so we can compare performance easily. I was asked the other day to provide my H-index . Problem was I have never heard about it before (only my fault). Just a wikipedia query later it turned out the idea was quite simple. H-index was proposed by Jorge E. Hirsch from UCSD and it is sometimes called Hirsch index or Hirsch number too. This is how it is obtained: Take your publications list and sort it by the number of citations. Now start counting papers from the top (most cited paper) and continue down till the number of citations is lower than the count of papers. The current count (or one less) is your H-index. So an H-index of, let's say, ten means that person...

I've heard some news about troubles with VirtualBox when running on Snow Leopard. It was too late for me as I've just upgraded a couple of my systems. So I installed VirtualBox and I created a sample Ubuntu 9.04 system from scratch. Everything ran smoothly. Network and USB access worked as expected too. I have no idea if there is trouble running a VM you created before upgrading to Snow as I have none. I used to be a fan of VMware's free VMplayer. Unfortunately there seems there is not a free version OS X. VirtualBox appears to do a nice job too. There is a quirk though, USB devices need to be registered to be used by the VM before you turn it on.

While reviewing some of the answers to one of the questions of Code Jam Round 1C, I've learned about this cool software . It can be run using Java Web Start , so you don't even need to install it. What is it about? I reckon it will make some Math teachers very very happy. In short, it is a drawing tool for geometry-oriented drawings. It can export to SVG or EPS too. Mastering on the use of the program may take a while, but I see lots of potential on this tool.

I've failed to make it to round 2 of Code Jam 2009 last weekend. I failed on getting the first problem (All your bases) right and that ate most of my available time. I was able to get the third one (Bribe the prisoners) right (bruteforcing it, not very elegant). So I used some time to get the first problem right after the contest :-) By the way, I later learned that there was a hidden constraint, as output value could not be larger than 10^18. That meant that maximum base could be 16 (as 1023456789abcdefg is base-17 is larger than that, 49030176097150555672 in case you're wondering). Here you have a simple solution in Java . And, yes, you can use Long.toString(String,int) instead of BigInteger, though the latter will cover a wider range than the problem statement requirements.

A few days ago I've got a shiny new MacBook Pro. Instead of coming with Snow Leopard installed, I've got a rebate on the price for the cost of the update to SL. I've installed Snow Leopard now but the disc does not contain a version of X11. As GIMP and Inkscape software depend on that I'm searching for the r ight version to install . I could use some help if you already know where to pull it from. Update : I'm happily running the GIMP on Snow Leopard. Contrary to my claim above, X11 is included on Snow Leopard, you'll find it in the Applications part of the optional install package.

Yep, it does sound odd, so a bit of an explanation may be welcome: I've bought me an electronic book reader a while ago (a Papyre 6.1 from Grammata). It is the same device as the Hanlin v3, Bebook, LBook and many other brand names given by sellers on different countries. The reading experience has been quite good. Actually it's been better than I expected. However, every now and then, like Windows 98, the system would refuse to turn page and freeze. After a few seconds [I suspect] the built-in watchdog timer quicks in and reboots the system. Total time is less than 30 seconds but the worst part is that you've lost the book page you were in. After checking several forums where many users complain about the same thing but no real solution was offered, I learned that an "alternative" firmware was available for a wide range of devices, including mine. Even better, there was a live version you could try before flashing it on your device. Who could ask for more? This...

I've just passed the qualification round of Code Jam with the feeling that I'm getting dumber every year. I only passed the first problem (Alien) and I've got stuck on the second problem (Water Basins). Third one (Welcome string) looked like the Speed Limit problem on 2008, but I did not attempt to do it. A plausible excuse is that I did not have the time ... Yes, I like that: I was busy working so I did not have time to waste playing this Code Jam thing. BTW, It was me the guy who asked about the error message on the Q&A. The error message said my solution file did not start with the string "Case #1:" but that was not true. The correct error message should have been that my solution file did not start with the string "Case #1: ". The difference being the space after the colon. Update: Here you have the three problems solved in Java.

A the moment of writing this, Gmail is giving the usual Server Error message you get when things go wrong. I hope the problem will be fixed soon. I've learned that Twiter can be useful whenever this happens. You can check by yourself with this query . There is also a reporting tool from Google that can come in handy.

As a Gmail user I've sometimes trouble with certain email alias unhappy of me sending from an SMTP server outside of our campus network. Another source of weirdness is the fact that while the From: field shows what I want, there is also a, sometimes not hidden, "On behalf of" that is broadcasting my gmail account even when I'm not interested on doing so. It's great that Gmail has added a new feature that allows Gmail servers to use your organization SMTP server as the outgoing SMTP server for your corporate email address. The two above mentioned problems are fixed then: You can send to email alias only intended for local users just right from Gmail (no nasty Outlook anymore, thanks). And secondly, there is only now the right From: mailbox. Cool!

From time to time we witness significant changes on how things are done. In terms of how we listen to music in the last ten years I've seen several interesting changes. Ten years ago I bought my wife her first MP3 player: It was Diamond Multimedia with 32 MB (yes, Megabytes) that could hold a couple CDs of 128kbps MP3 music. Since then on I've bought many other MP3 devices for my household. However, that marked the end of traditional media (CD-audio) for our portable uses. While MP3 players have been around for quite a while, it seems that Apple's iPod is now the king. And while kingdoms do not last long in this market I guess Apple has done something right. Many people (like myself) are device-centric. For quite a while I favored Creative players and while I've never bought music from iTunes, I've bought some software there. Meanwhile I've stopped buying from Creative after problems with several players. And now that I have time I've played a bit with anot...

It's been hectic times around here, mostly due to different changes at my workplace. Now it's time to start thinking on having some vacation. A summer trip seems a good idea but this year I've selected Norway : beautiful but expensive. While there are tons of information on-line, I have found details are a bit sketchy. This is likely due to the fact I'm interested on cheap accommodation. Maybe the average wages in Norway are much higher than in my home country, Spain. I've got some trouble getting things done online. There seems to be some odd behavior and this booking website , when browsed with Firefox on Ubuntu 8.04. The worst thing is that it was this the browser I was using when booking my flight with Norwegian.com and I was offered a very competitive car-rental price at the end of the airplane booking process. Unfortunately when trying to go to book the car I was offered an almost empty page. I was wrong when I thought I could go back to the former page too. S...

No, I'm not going to complain about the output quality (at least not yet as I'm still waiting for my order). What I want to complain about is the fact that your iPhoto Book orders do not show up on your Apple Store account. And apparently this oddity has been happening for quite a while . That means that there is no way for you to know about your order status. Of course there is a confirmation email sent to your Apple ID email but, what if your .mac account has expired? (then you no longer have access to that email). To make things worse, once 1-click order has been activated iPhoto will not ask you for an additional confirmation when issuing a new order (I guess that's the 1-click beauty once your Apple ID email account works nicely). Calling customer service did not help much, as I was assured my credit card was not billed and somehow I had no pending orders. Calling my bank gave me another version: My credit card was billed (and apparently my order was taking longer tha...

Not yet very affordable, but better than I expected. This is my opinion after buying an ebook reader. Mine is branded Papyre 6.1 but it's named Hanlin v3 in other countries. It's manufactured in China (what a surprise!) and it runs Linux (it has an ARM processor). Definitely worth watching at. However I have not used it for more than a few minutes so I do not have an opinion about the long term usefulness of the device. But if it delivers what I've seen in the tests it is more than worth it. Now I'm sorry but I'm back to reading, please do not disturb. Update: The reading experience has been better than expected. And the availability of contents has also been better than expected. What I have not find, however, is a shop with the latest books. But that only meant some books cannot be bought but they might be available somewhere ... For example, I was reading a paper copy of this book in Spanish. And I had no trouble finding an electronic version. There is a cheap...

Years ago, in a distant galaxy, I was a member of ICSI . Now I've been surprised about one their offerings to the community: A network analyzer . It's Java-based so it won't work unless you have Java support in your browser and you're happy running digitally signed code. You may learn a couple of things about your network connection.

A succession of breathtaking sequences shot from the air is the newest release by this widely awarded photographer. It's really worth watching. You can get the movie for free! Movie is available in theaters all over the world (but apparently not in USA) and also in YouTube in HD . Although the beauty of the images might be better enjoyed on the big screen, you can have a look at it on-line. What amazes me is that it is the creators of the movie who decided to release it on YouTube at the same time than in theaters. The release details were given on a press conference . The movie has been sponsored by PPR , a French multinational in the fashion business.

I've found the network transfers to take forever on this device. Between 1 and 2 Mbytes/second is really slow by todays standards. It means around 4GB per hour. I'm happy with the torrent download functionality I mentioned on a previous entry but there is a catch: What if your download contains a sequence of RAR files? Yep, it happened to me with a 16GB download. Moving this back and forth to a PC would took more than 8 hours!! So the obvious idea is ... why not to have unrar command on the SPP? And this is what I did. I looked for the source code , and using a buildroot ext2 image file I compiled unrar command . Now I can telnet to my box and launch it without the need of moving files back and forth. It's not lightspeed but it's minutes instead of hours. The other improvement was to add SSH functionality by borrowing dropbear binary from OpenWRT project . Please have a look at dropbear documentation so you can install in properly on your system (a few files and links ...

My old analog camera is also giving me trouble. The symptom was that many pictures had just a small fraction of the total field. This can happen when shooting with flash if the sync speed is not correct (flash fires when shutter is half-open only). However this time I was shooting outdoors without a flash. After a few iterations with Google led my to a photo on Wikipedia with exactly the same type of residue I've found on my camera. A few more searches led me this article that explains the causes of the problem and a possible fix. Aging and heat turn a piece of foam inside the camera guts into an oily tar that ruins the shutter operation. Did you think you can keep on using your old camera, maybe not if it as a twenty years old Canon EOS.