Algorithms for the Masses by Julian M Bucknall

Way back when, so long ago I can't remember, I bought a product called Passwords Plus from DataViz. The product is an application for storing passwords, PINs, and the like, and supported Palm devices as well as providing a Windows desktop application. At the time I had a Sony Clié NR70V, which I carried everywhere with me, and so the app made sense.

Since then, of course, Palm OS devices have fallen by the wayside, and indeed the latest Palm Desktop app doesn't even support Windows Vista 64-bit which means you can no longer synchronize. So although I no longer use my Clié, I've still kept on using the Windows app, despite it getting somewhat long in the tooth. But, with 300-odd items in the database, there was no way I was going to give it up without good reason.

That reason came 10 days ago, a new iPhone 3GS. Now, I had another device that I carried around that called out for a password app (for some reason the Windows Mobile phone I had before didn't engender such feelings). So I looked online for recommendations (iPhone app, with Windows desktop app, plus sync between them, and it had better have some kind of import). After a little research, I found one: SplashID from SplashData.

The app promised import of CSV files and Passwords Plus could provide them. Pretty obviously, though, those CSV file formats would be different, but I'm nothing if not a programmer.

The CSV route proved abortive (the import CSV feature of SplashID was pretty limited, given the amount of configuration I'd done on the Passwords Plus data), but there was an alternative that proved better: SplashID allowed you to import data from "vid" files, usually encrypted. And if they weren't? They were a more complete CSV file format that could define all of the data that SplashID wanted. So I created an unencrypted "vid" file from my Passwords Plus data, and voilà!

The rest of this article is merely a definition of the data format of an unencrypted vid file. No need to read it if you're not interested, but it'll serve as an information repository for those who care (for instance, me, in a couple of years' time).

The unencrypted vid file is a text file, with most records comprising comma-separated values. There are four sections. First is the file header record: "SplashID vID File -v3.0". The next record consists of a single "F". I think this is something to do with the password to the file, since if I leave it out, I get some bizarre behavior (SplashID will ask for a password if this record is missing). Then there is a set of template or type records, followed by a set of data records. These two kinds of records can be interleaved, so long as the type record appears before a data record that uses it. Both type and data records are CSV records, with the first field being "T" for a type record, and "F" for a data record.

The fields for a type record are:

The fields for a data record are:

The rules for CSV files apply here. If a value has an embedded comma, the whole value must be surrounded by double quotes. If the value has a double quote, the whole value is again surrounded by double quotes, and the embedded double quotes are escaped with another double quote mark. So if a value was "Mon Repos", Denver, it would be represented in the vid file as """Mon Repos"", Denver".

To create a vid file from a CSV export from Passwords Plus merely required rearranging the "columns" in the CSV file and calculating the hidden fields bit mask. (Despite my prowess as a programmer, I just used Excel this time.) To make it easy for myself later I created a type called "Imported" (and chose some icon for it). I then imported the vid file into an empty SplashID database, and then synced it with my iPhone.

(There were about 6 data records I had to futz with since Passwords Plus allows for 10 fields per record, whereas SplashID only has 8 — there are nominally 10, but 2 are taken up with the Name/Description and the modified date.)

Now playing:
Orzabal, Roland - Hypnoculture
(from Tomcats Screaming Outside)

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Despite getting a sheet-fed scanner, I still use my flat-bed scanner to scan, mainly photos. The last couple of times we've been home, Mum has given us some old photos. Well, not necessarily given, but lent so that I could scan them and, if needed, print better ones.

The one on the right there, for example, was taken when I was 15 or 16, standing in front of the front door of our house at the time. 1972 or '73. If I recall correctly it was taken by my Uncle Ty, who still remains an avid photographer, though obviously at the time it was on film.

Looking at it now, it looks like I'm just about to sign up with The Style Council, or maybe even The Jam. Steely gaze under a fringe, and a polo neck. Damn cool or what?

To contrast that photo, here's a much older one:

This was taken in 1908 and shows my great grandfather and his family. My great grandmother, seated there, was pregnant with my grandmother, Mum's mother. Despite the general mortality rates at the time, all the children survived and grew up to be adults. Three of the lads even joined up for the first World War, although one of them was too young (Mum says he was found out and my great grandmother had to travel to France to pick him up). My great grandfather was a policeman in a village called Wolston, just outside Coventry.

I never knew any of them except for the girl seated on the right, who was my great aunt Annie, who died at about the same time as my photo above was taken. Unfortunately, I've misplaced the notes I took on all their names so I'll have to ask next time I phone my parents.

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About three months ago, as I was trying to gather documentation for my taxes to take along to my accountant, something finally snapped. I had all these invoices and statements and papers in a big old folder, and I was flipping through them, trying to find documents relevant to my taxes. In the closet in my office there's a bunch of other folders for previous years too. Ditto, the basement (oh, heck, I really need to sort it all out down there). It's a big mess.

I should scan them I thought, but the thought of digitizing them all with my flat-bed scanner in some manner was decidedly unappetizing. I knew it would never happen.

So I looked online for other solutions. After some browsing I came across the Fujitsu ScanSnap S300. It sounded ideal: a sheet feed scanner that automatically converts scans to PDF, and OCRs the images if you so wish. It does both sides of the paper at once and discards blank sides automatically. It also came with a document management application (ScanSnap Organizer) that helped store and organize (through the drag and drop of thumbnail images no less) your scanned documents. I ordered one from Amazon.

When it arrived, I set it up and started scanning some of my collected invoices/statements to see how it worked and what the results were like. It's fast, let's put it like that. I didn't bother with the OCR part of the scanning process (I don't care to actually search my phone bills, for example). A sheet goes in, you hit the button on the front, it scans, and automatically converts to a PDF on the PC, and puts it in the app's document folder to be sorted/organized. Very quick, very simple.

For my particular use scenario then, it's well recommended, but as I said, I haven't tried the OCR parts of the software, nor have I tried the business card scanning side of things. Anyway, after three months use I have an ever-growing set of PDFs, nicely organized on an external drive, and my paper shredder is getting more use than ever before. Every time an invoice comes in and is paid, I scan and shred it straight away.

(Note: there are several models in the ScanSnap series. I just chose the one with the smallest footprint. It's supposed to be "portable" as well, though I can't imagine taking it on a business trip.)

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Last night, I had to draw a regular hexagon in Adobe Illustrator, Now, I remember from my school days how to draw one with a compass and ruler (draw a circle with the compasses, and then select a point on the circumference and mark off radii with the compasses, going round the circle; you'll mark off six intersections and then connect them with straight lines: voilà!), but I don't have any compasses in Illustrator.

(UPDATE: OK, now I feel silly. There's a Polygon tool in Illustrator. It's part of the rectangle tool list in the toolbox. Click it to select it, click on the artboard to set the number of sides, and then draw it. Oh well.)

A moment's reflection gave me an answer.

• Draw a horizontal line
  
• Copy that line to the clipboard
• Paste a copy of the line
• Rotate it 60°, move it so it touches the horizontal line on the left
  
• Paste a copy of the line
• Rotate it -60°, move it so it touches the horizontal line on the right
  

You now have half a hexagon.

• Using the lasso tool, lasso the left corner, and join the line segments (use Corner as the method)
  
• Lasso the right corner and do the same
  

The lines now form a path.

• Copy the half hexagon to the clipboard
• Paste a copy
• Reflect the copy horizontally
• Move the copy so that it touches the other half
• Join the two halves with the lasso tool
  

You now have a regular hexagon. The lines form a closed path and so you can color the perimeter and the interior as desired.

The magic rotation angle is the exterior angle for the sides on a regular hexagon. If you want another regular polygon, calculate the relevant exterior angle (360 divided by the number of sides) and proceed as before. If the number of sides is not even you won't be able to use the reflection trick to save time, but will have to paste/rotate every side as required. For example, here's a regular pentagon (exterior angle = 72°):

Obviously, if the number of sides doesn't divide into 360° exactly, there will be some fudging at the corners to make it all fit properly.

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I write a monthly column for PCPlus, a computer news-views-n-reviews magazine in the UK (actually there are 13 issues a year — there's an Xmas issue as well — so it's a bit more than monthly). The column is called Theory Workshop and appears in the back of every issue. When I signed up, my editor and the magazine were gracious enough to allow me to reprint the articles here after say a year or so. After all, the PDFs do appear on each issue's DVD after a couple of months. When I buy the current issue, I'll publish the article from the issue a year ago. Since I've just bought the issue for June 2009, here's June 2008's article.

I confess this was a quick article to write. I'd already done a great deal of research on drawing binary trees for a series of blog posts I was writing about red-black trees on my old blog, so it was just a case of recasting what I'd already written into the PCPlus "style" and creating a set of new images.

The red-black tree posts I'd been writing at the time are here: 1, 2, 3, 4, 5, 5 bis.

This article first appeared in issue 269, June 2008.

You can download the PDF here.

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Some notes on our trip to England last week in no particular order or significance.

• Flew with United. On the way out we had a 767 with the new lay-flat Business seats (no, we weren't in Business, just in Economy Plus). Man, they look good. On the way back it was a 777, with the older Business section.
• Had one of the new Audi A4s as a rental. Nice car, I must say, even pretending I wasn't a Audi fan anyway. Found out after we'd got to the hotel in the second half of the week that the reverse had a sensor for detecting how close the rear of the car was to any obstruction. It beeped quicker the closer you got, until the point where it was a continuous tone indicating that you were about to hit something. Magic. Absolutely and utterly handy.
• Drove up to North Yorkshire where my parents live using the M25, M1, and then A1. I couldn't believe the number of roadworks going on. I pity everyone using the M25 north of the M4 for the next year. Bloody awful set of roadworks. Because of that we came back down on the M6/M40: much nicer.
• We love M&S Simply Food. Best sandwiches on the motorway. Nuff said.
• The buttercups in the fields in Swaledale were absolutely beautiful.
• Because our usual hotel in Windsor was fully booked and since we liked being close to the town, I booked a room at The Christopher Hotel in Eton instead. For some reason they upgraded us to one of their suites, and I must say, apart from the distance to the Long Walk, we enjoyed it very much. The parking was amazingly cramped though; I got good use of the reverse sensor in the car. Recommended.
• We saw a most excellent production at the Theater Royal: an adaptation of Brief Encounter, set to music and songs by Noël Coward. Very good indeed. (To which I add, thank heavens we weren't there this week instead: there's a production of 'Allo 'Allo.  Shudder.)
• Tried Loddon Hullabaloo Best for the first time (it was the brew in the hotel bar). Not a bad bitter at all. Also partook of a Black Sheep Best, an Abbot Ale, but missed out on a London Pride (although United have cans of it on their flights to/from London).
• We hate Terminal 1 at Heathrow with a passion. United used to use Terminal 3, which is better (at least you can get a good breakfast at Chez Gerard there). Next time, we'll have a Prêt-à-Manger sandwich for breakfast — the cafes all serve bloody awful breakfasts. (This time was the turn of The Tin Goose: they were out of the hollandaise for the Eggs Benedict. I had a remarkably overdone fried egg in my "English" breakfast instead. Bleugh.)

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We came home after a relaxing week-long visit to England to find that my direct debit to our gym was bounced by my Wells Fargo credit card. I logged on to my account on the bank's website to find that someone in Atlanta, GA, had been "using" my credit card to rack up about $7,000 in charges, all within a couple of hours on the day we flew out of Denver. I was at 38,000 ft when the fraud occurred. The charges had triggered the automated fraud system, and Wells Fargo put a hold on the card. From which, of course, automatic debit transactions started failing including the one for the gym.

(The story so far is bittersweet: every time I try to use my Wells Fargo credit card outside the US, it's automatically refused and the card is put on hold. I have to remember to phone them before I travel to tell them that I'll be using it outside the country so that this doesn't happen. I'd forgotten to do that this particular trip.)

I phoned up a very nice lady in the fraud department at Wells Fargo, sorted out which charges were fraudulent, and she then cancelled the card completely. They'll be sending me a new card in a few days with a new account number and transfer all the valid charges to it. I am grateful that I didn't get the third degree about who had access to my credit card, and was it possible that someone could have used it without my knowledge? (I kid you not, but this happened with US Bank when I saw fraudulent charges on that last year.)

Anyway, this isn't particularly about that. It's about what went wrong. I'm guessing that these charges were made with a fraudulent physical card, the magnetic stripe on mine had been copied and then transferred. I'm assuming "physical" since most if not all online stores require the CVV (that 3-digit number printed on the back) and mine has worn away and is illegible (I keep my cards in my wallet in the back pocket and, let's just say, it's a hostile environment...). I don't use this card for online purchases at all. So, someone duped the card and eventually used it in an orgy of purchases until it was locked out.

The interesting thing for me is that I'd just been to England where all credit cards are smart cards with those little chips embedded in them. The same for Europe as a whole, for that matter. It's not easy to dupe such a card, not only for that particular reason but for the additional one that when you pay for things, say a meal in a restaurant, you have the card in sight at all times. The waiter will come to the table with a wireless card reader that will debit your card there and then: you put the card in the device, chip first to allow the machine to validate the chip, and then type the PIN, and the transaction goes through.

Why this technology is not available in the US, I have no idea. Certainly, the credit cards are more expensive to produce and program (and the merchants' readers would all have to be changed too), but compared to losses due to physical fraud I'd have though it would be worthwhile. Of course, this does nothing to alleviate online credit card fraud where no physical card is present.

The other thought I have is that, despite considering myself to be a careful credit card user, I've now been defrauded on two separate occasions within the past 13 months. (The last time was using a duped card too, in a gas station to get fuel.) Am I unusual? If not, then no wonder credit card interest rates are so high — the banks have to pay for the frauds from using unsecure systems.

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It's time for a laugh.

Way back when, I went to King's, London, to take Mathematics as an undergraduate degree. While I was there, I joined the King's Mathematical Society (a.k.a. MathSoc), as one would, and in a fairly short amount of time I became the Treasurer of said society. I wasn't completely out of my senses; my best friends also gained positions: Phil Allen (the guy dead center with the gown) was President, and Stuart Kelly (immediately to my left) was Social Secretary. Rounding up the MathSoc team were Anne-Marie Critchard (to my right) as VP, and Gail Croston (two over on my right) as Secretary.

Looking at this photo now (click it for a larger version), I'm reminded about how long ago it was. For a start, you can see it in the 70s fashions, especially the hair. Oh man. Another is that I'm having real problems remembering people's forenames (the photo comes with surnames). Sure my "inner circle" I can remember, but, for example, the guy 4th row back, furthest left, was next door neighbor in the halls of residence on Champion Hill and for the life of me I can't recall his first name (Simon Rees?). Ditto the guy in the first row, furthest right, was my mentor when I started, but again memory fails me as to the name (Mark Harvey?).

One name I do remember is second row, furthest left: Dr Paul Davies, as he was then. Famous in layman's circles for writing philosophical books that explore the boundaries (if any) between what physics knows and what it doesn't. He taught me Special Relativity in my second year and the interesting thing about the final exam was that you could take your notes in and refer to them if need be.  Also penultimate right, same row, is Prof. John Taylor who taught me Neural Networks (not the computer science thing, but a mathematical treatment, at least as far as I remember) in my third year. No fault of his, but it was the only course I failed — I couldn't engender any enthusiasm for it, despite the infamous first lecture of the course when he brought in Tupperware container containing a human brain dripping with formaldehyde solution.

So, if you're in that photo, post a comment here, or send me an email. I'd love to hear from you.

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I write a monthly column for PCPlus, a computer news-views-n-reviews magazine in the UK (actually there are 13 issues a year — there's an Xmas issue as well — so it's a bit more than monthly). The column is called Theory Workshop and appears in the back of every issue. When I signed up, my editor and the magazine were gracious enough to allow me to reprint the articles here after say a year or so. After all, the PDFs do appear on each issue's DVD after a couple of months. When I buy the current issue, I'll publish the article from the issue a year ago. Since I've just bought the issue for May 2009, here's May 2008's article.

I had a good deal of fun writing this article. A great deal. Not only in the writing of it, but in the drawing of the figures. All my Adobe Illustrator skills came to fore, not that I have that many of course, and it was a blast drawing the curves and the "beads" travelling along straight lines and everything coming out just right. (Since Illustrator just does cubic splines, the quadratic spline images were faked with cubic ones and I'm still amazed it all worked out.)

The topic was also fascinating as well. The rivalry between two designers at French car manufacturers in the early 60s. PostScript and the AppleWriter. I love typography (I've been known to put down hard-earned cash for beautiful fonts) and writing about how the glyphs are rendered on a screen or on paper was a delight. Rereading it now at such a remove, I feel my enthusiasm for the subject comes though strongly in the text. One of my more favorite articles, without a doubt.

This time I was determined to get the text right and so I pointed out to my editor that the narrative contained accented characters (Bézier, Citroën) and that the typesetter had to take special care. I'm glad to say everything turned out just right. Awesome: many thanks to Richard, my editor, and the anonymous typesetter.

This article first appeared in issue 268, May 2008.

You can download the PDF here.

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Last night, I read about the new netbook OS, open source but funded by Intel, called Moblin. It’s been designed and implemented especially for Intel Atom-based netbooks, such as the Dell Mini 9 (Inspiron 910), and so I decided to give it a try.

So, I followed the excellent instructions on the website, downloaded the disk image, set myself up with a bootable USB drive containing said image, and booted the Mini.

The OS’ UI is very intuitive and, dare I say it, cute for a netbook. It makes excellent use of the limited screen estate hiding the top toolbar when not in use. Icons are simple, well-designed and large. Easy to click, from Fitt’s Law. The applications look good and run well too, hiding the arcana of Linux running underneath.

Unfortunately, the network access leaves a lot to be desired. The wi-fi just doesn’t work with the Mini 9, period, and other netbooks seem to have the same issues. The wired connection is only recognized if the cable is plugged in when you boot, and at that the built-in browser doesn’t find any URLs. That’s a real shame because without internet access all of the “mobile” apps, like the browser, twitter, etc, just don’t work in any meaningful way. Flash is not provided, so you must download it, which I couldn’t of course.

So, regretfully, I powered off the Mini and rebooted back into Windows 7, which, I must report, just works on the Mini. No weirdnesses, everything just worked. Intel have a little way to go methinks, but I’ll try it again in a few weeks.

(Interesting aside: I’m writing this blog post in Windows Live Writer on my Mini. Apart from the cramped keyboard, no issues.)

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