Shallow Thoughts : : writing

Akkana's Musings on Open Source Computing and Technology, Science, and Nature.

Mon, 04 Sep 2017

Jumpstarting the Raspberry Pi Zero W: Now Available via Humble Bundle!

[Raspberry Pi Zero W] My new book is now shipping! And it's being launched via a terrific Humble Bundle of books on electronics, making, Raspberry Pi and Arduino.

Humble Bundles, if you haven't encountered them before, let you pay what you want for a bundle of books on related subjects. The books are available in ePub, Mobi, and PDF formats, without DRM, so you can read them on your choice of device. If you pay above a certain amount, they add additional books. My book is available if you pay $15 or more.

You can also designate some of the money you pay for charity. In this case the charity is Maker Ed, a crowdfunding initiative that supports Maker programs primarily targeted toward kids in schools. (I don't know any more about them than that; check out their website for more information.)

Jumpstarting the Raspberry Pi Zero W is a short book, with only 103 pages in four chapters:

  1. Getting Started: includes tips on headless setup and the Linux command line;
  2. Blink an LED: includes ways to blink and fade LEDs from the shell and from several different Python libraries;
  3. A Temperature Notifier and Fan Control: code and wiring instructions for three different temperature sensors (plus humidity and barometric pressure), and a way to use them to control your house fan or air conditioner, either according to the temperature in the room or through a Twitter command;
  4. A Wearable News Alert Light Show: wire up NeoPixels or DotStars and make them respond to keywords on Twitter or on any other web page you choose, plus some information on powering a Pi portably with batteries.

All the code and wiring diagrams from the book, plus a few extras, are available on Github, at my Raspberry Pi Zero Book code repository.

To see the book bundle, go to the Electronics & Programming Humble Bundle and check out the selections. My book, Jumpstarting the Raspberry Pi Zero W, is available if you pay $15 or more -- along with tons of other books you'll probably also want. I already have Make: Electronics and it's one of the best introductory electronics books I've seen, so I'm looking forward to seeing the followup volume. Plus there are books on atmospheric and environmental monitoring, a three-volume electronic components encyclopedia, books on wearable electronics and drones and other cool stuff.

I know this sounds like a commercial, but this bundle really does look like a great deal, whether or not you specifically want my Pi book, and it's a limited-time offer, only good for six more days.

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[ 13:21 Sep 04, 2017    More writing | permalink to this entry | comments ]

Sun, 16 Jul 2017

Translating Markdown to LibreOffice or Word

For the Raspberry Pi Zero W book I'm writing, the publisher, Maker Media, wants submissions in Word format (but stressed that LibreOffice was fine and lots of people there use it, a nice difference from Apress). That's fine ... but when I'm actually writing, I want to be able to work in emacs; I don't want to be distracted fighting with LibreOffice while trying to write.

For the GIMP book, I wrote in plaintext first, and formatted it later. But that means the formatting step took a long time and needed exceptionally thorough proofreading. This time, I decided to experiment with Markdown, so I could add emphasis, section headings, lists and images all without leaving my text editor.

Of course, it would be nice to be able to preview what the formatted version will look like, and that turned out to be easy with a markdown editor called ReText, which has a lovely preview mode, as long as you enable Edit->Use WebKit renderer (I'm not sure why that isn't the default).

Okay, a chapter is written and proofread. The big question: how to get it into the Word format the publisher wants?

First thought: ReText has a File->Export menu. Woohoo -- it offers ODT. So I should be able to export to ODT then open the resulting file in LibreOffice.

Not so much. The resulting LibreOffice document is a mess, with formatting that doesn't look much like the original, and images that are all sorts of random sizes. I started going through it, resizing all the images and fixing the formatting, then realized what a big job it was going to be and decided to investigate other options first.

ReText's Export menu also offers HTML, and the HTML it produces looks quite nice in Firefox. Surely I could open that in LibreOffice, then save it (maybe with a little minor reformatting) as DOCX?

Well, no, at least not directly. It turns out LibreOffice has no obvious way to import an HTML file into a normal text document. If you Open the HTML file, it displays okay (except the images are all tiny thumbnails and need to be resized one by one); but LibreOffice can't save it in any format besides HTML or plaintext. Those are the only formats available in the menu in the Save dialog. LibreOffice also has a Document Converter, but it only converts Office formats, not HTML; and there's no Import... in LO's File. There's a Wizards->Web Page, but it's geared to creating a new web page and saving as HTML, not importing an existing HTML-formatted document.

But eventually I discovered that if I "Create a new Text Document" in LibreOffice, I can Select All and Copy in Firefox, followed by Paste into Libre Office. It works great. All the images are the correct size, the formatting is correct needing almost no corrections, and LibreOffice can save it as DOCX, ODT or whatever I need.

Image Captions

I mentioned that the document needed almost no corrections. The exception is captions. Images in a book need captions and figure numbers, unlike images in HTML.

Markdown specifies images as

![Image description][path/to/image.jpg)

Unfortunately, the Image description part is only visible as a mouseover, which only works if you're exporting to a format intended for a web browser that runs on desktop and laptop computers. It's no help in making a visible caption for print, or for tablets or phones that don't have mouseover. And the mouseover text disappears completely when you paste the document from Firefox into LibreOffice.

I also tried making a table with the image above and the caption underneath. But I found it looked just as good in ReText, and much better in HTML, just to add a new paragraph of italics below the image:


*Image description here*

That looks pretty nice in a browser or when pasted into LibreOffice. But before submitting a chapter, I changed them into real LibreOffice captions.

In LibreOffice, right-click on the image; Add Caption is in the context menu. It can even add numbers automatically. It initially wants to call every caption "Illustration" (e.g. "Illustration 1", "Illustration 2" and so on), and strangely, "Figure" isn't one of the available alternatives; but you can edit the category and change it to Figure, and that persists for the rest of the document, helpfully numbering all your figures in order. The caption dialog when you add each caption always says that the caption will be "Illustration 1: (whatever you typed)" even if it's the fourteenth image you've captioned; but when you dismiss the dialog it shows up correctly as Figure 14, not as a fourteenth Figure 1.

The only problem arises if you have to insert a new image in the middle of a chapter. If you do that, you end up with two Figure 6 (or whatever the number is) and it's not clear how to persuade LibreOffice to start over with its renumbering. You can fix it if you remove all the captions and start over, but ugh. I never found a better way, and web searches on LibreOffice caption numbers suggest this is a perennial source of frustration with LibreOffice.

The bright side: struggling with captions in LibreOffice convinced me that I made the right choice to do most of my work in emacs and markdown!

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[ 14:12 Jul 16, 2017    More writing | permalink to this entry | comments ]

Thu, 06 Jul 2017

Writing a Book on the Raspberry Pi Zero W

It's official: I'm working on another book!

This one will be much shorter than Beginning GIMP. It's a mini-book for Make Media on the Raspberry Pi Zero W and some fun projects you can build with it. [Raspberry Pi Zero W]

I don't want to give too much away at this early stage, but I predict it will include light shows, temperature sensors, control of household devices, Twitter access and web scraping. And lots of code samples.

I'll be posting more about the book, and about various Raspberry Pi Zero W projects I'm exploring during the course of writing it. But for now ... if you'll excuse me, I have a chapter that's due today, and a string of addressable LEDs sitting on my desk calling out to be played with as part of the next chapter.

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[ 09:50 Jul 06, 2017    More writing | permalink to this entry | comments ]

Thu, 21 Nov 2013

Dinosaur Doggerel

I woke up thinking about dinosaurs.

Specifically, Pachycephalosaurus, the bone-headed dinosaur, and her long-crested cousin Parasaurolophus (pictured at right).

The previous night, I had been reading The Know-It-All, A. J. Jacob's entertaining account of his adventures reading the whole Encyclopedia Britannica. I'd left off in the Ps, which included a very short entry on Pachycephalosaurus (A.J. is not particularly into dinosaurs).

Drifting along in a typical insomniac "I wish I could get back to sleep" haze, I couldn't help noticing that Parasaurolophus was six syllables -- in fact, it was a double dactyl.

And that meant it was a prime candidate for my favorite verse form, double-dactylic doggerel, a form with fairly strict rules which require, among other things, that the second line be a double-dactylic proper name. And as double-dactylic junkies know, once you've noticed a double-dactylic name, you can't rest until it's turned into a poem.

So now I couldn't sleep because I was thinking about Parasaurolophus. Now, even aside from its mellifluous name, Parasaurolophus and the whole Hadrosaur family are pretty interesting. The biggest puzzle is why they had those elaborate bony crests. Decoration for mating purposes? Fighting, like horns and antlers on modern hoofed mammals? But in the late 1990s, CT scans of hadrosaur fossils revealed long air passages inside the crests of many Hadrosaurs, including Parasaurolophus ... and those air passages were connected to the nasal passages. That led to suggestions that the crests might have been tuned for sound production -- a built-in wind instrument.

[computer model of Parasaurolophus crest] In Scientists Use Digital Paleontology to Produce Voice of Parasaurolophus Dinosaur a team at Sandia made computer models of the air passages, and you can even listen to sound files of what Parasaurolophus might have sounded like. The sound is wonderful, like a trombone. Sandia's pages use a, <embed> tag that didn't work for me in Firefox, so if you have trouble with their links, I've separated out the wav file URLs: songLQ.wav (588k) and a higher quality version, song2.wav (2.7M).

Anyway, I never did get back to sleep, but I did end up with some insomniacal doggerel:

Dinosaur, schminosaur
How do you use that
Magnificent crest?
"I play trombone in the
Dinosaur orchestra
All hadrosaurs play, but
I am the best."

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[ 16:49 Nov 21, 2013    More writing | permalink to this entry | comments ]

Thu, 13 Jan 2011

Article: Arch Linux

My latest article on Linux Planet is a review of Arch Linux.

I've been quite favorably impressed with Arch. It's a good, solid, straightforward distro that's very well suited to folks who like to administer their systems via the command-line -- or who want to learn how to do that.

I've been running it on my laptop for a few months, because it has excellent performance, without a lot of the bloatware you see in a lot of other distros, and it boots fast.

The only real problem I've had involves fonts. I see nasty font artifacts -- sometimes subtle, a line or a few pixels missing from certain letters -- but sometimes severe, as in this screenshot or this one. In the article I talk about some solutions I've found that make the problems less bad, but I haven't found any way to make them go away entirely.

Unfortunately, since the font problems are worst inside browsers and I use my laptop for presentations at conferences, this may eventually drive me off Arch. I hope not -- I hope I can find a solution -- because otherwise, Arch has been nothing short of a pleasure.

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[ 20:36 Jan 13, 2011    More writing | permalink to this entry | comments ]

Fri, 15 Oct 2010

Snakes on a Couch! Using Python with CouchDB

Part II of my CouchDB tutorial is out at Linux Planet. In it, I use Python and CouchDB to write a simple application that keeps track of which restaurants you've been to recently, and to suggest new places to eat where you haven't been.

Snakes on a Couch, Part 2: Where do you want to eat?

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[ 21:00 Oct 15, 2010    More writing | permalink to this entry | comments ]

Thu, 23 Sep 2010

Snakes on a Couch! Using Python with CouchDB

I've been learning CouchDB, the hot NoSQL database, as part of my new job. It's interesting -- a very different mindset compared to classic databases like MySQL.

There's a fairly good Python package for it, python-couchdb ... but the documentation is somewhat incomplete and there's very little else written about it, and virtually no sample code to steal.

That makes it a perfect topic for a Linux Planet tutorial! So here it is, Part 1:

Snakes on a Couch! Using Python with CouchDB.

I have a rather fun application for the database I introduce in the article, but you'll have to wait until Part 2, two weeks from now, to see the details.

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[ 11:55 Sep 23, 2010    More writing | permalink to this entry | comments ]

Thu, 09 Sep 2010

Hugin part 2: Rescuing Difficult Panoramas

[tricky Hugin panorama] Part 2 in my Hugin series is out, in which I discuss how to rescue difficult panoramas that confuse Hugin.

Hugin is an amazing program, but if you get outside the bounds of the normal "Assistant" steps, the user interface can be a bit confusing -- and sometimes it does things that are Just Plain Weird. But with help from some folks on IRC, I found out that a newer version of Hugin can fix those problems, and worked out how to do it (as well as lots of ways that seemed like they should work, but didn't).

Read the gory details in: Hugin part 2: Rescuing Difficult Panoramas.

There will be a Hugin Part 3, and possibly even a Part 4, discussing things Hugin can do beyond panoramas.

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[ 14:58 Sep 09, 2010    More writing | permalink to this entry | comments ]