Anyway, it’s easy enough to <Alt -F2> gnome-set <ret>, and I’ve never lost any work or had an episode of Futurama ruined or anything…

In file included from /usr/include/c++/4.4/bits/stl_algobase.h:67,
                 from /usr/include/c++/4.4/bits/char_traits.h:41,
                 from /usr/include/c++/4.4/ios:41,
                 from /usr/include/c++/4.4/ostream:40,
                 from /usr/include/c++/4.4/iostream:40,
                 from ../src/Flipper.cpp:1:
/usr/include/c++/4.4/bits/stl_iterator_base_types.h: In instantiation of ‘std::iterator_traits > > >’:
/usr/include/CGAL/centroid.h:833:   instantiated from ‘CGAL::CGALi::Dispatch_centroid > >, CGAL::Point_2 > > >’
../src/Flipper.cpp:102:   instantiated from here
/usr/include/c++/4.4/bits/stl_iterator_base_types.h:127: error: no type named ‘iterator_category’ in ‘class CGAL::Point_2 > >’
/usr/include/c++/4.4/bits/stl_iterator_base_types.h:128: error: no type named ‘value_type’ in ‘class CGAL::Point_2 > >’
/usr/include/c++/4.4/bits/stl_iterator_base_types.h:129: error: no type named ‘difference_type’ in ‘class CGAL::Point_2 > >’
/usr/include/c++/4.4/bits/stl_iterator_base_types.h:130: error: no type named ‘pointer’ in ‘class CGAL::Point_2 > >’
/usr/include/c++/4.4/bits/stl_iterator_base_types.h:131: error: no type named ‘reference’ in ‘class CGAL::Point_2 > >’

Translation: you don’t need to include ‘centroid.h’.

Clearly, the Java guys took some shortcuts here, because the polygon ends up including a lot of interior segments that you don’t really want, etc. However, filling it using a nonzero winding rule covers a lot of sins. And I can understand why they committed those sins, since it’s kinda hard to do in general. Read the CGAL page about offsetting for an intro. Sometime I’ll have to investigate the shortcut methods in the OpenJDK source; looking at this output, I’m definitely curious.

Unfilled

Filled

import java.awt.BasicStroke;
import java.awt.Shape;
import java.awt.geom.Path2D;
import java.awt.geom.PathIterator;

public class StrokePath
{
    public static void main(String[] args)
    {
        // set line width to 6, use bevel for line joins
        BasicStroke bs = new BasicStroke(6.0f, BasicStroke.CAP_SQUARE, BasicStroke.JOIN_BEVEL);

        // create a path for the input
        Path2D p = new Path2D.Float();
        p.moveTo(50.0, 50.0);
        p.lineTo(65.0, 100.0);
        p.lineTo(70.0, 60.0);
        p.lineTo(120.0, 65.0);
        p.lineTo(40.0, 200.0);

        // create outline of wide lines by stroking the path with the stroke
        Shape s = bs.createStrokedShape(p);
        // output each of the segments of the stroked path for the output polygon
        PathIterator pi = s.getPathIterator(null);
        while (!pi.isDone())
        {
            pi.next();
            double[] coords = new double[6];
            int type = pi.currentSegment(coords);
            switch (type)
            {
            case PathIterator.SEG_LINETO:
                System.out.println(String.format("SEG_LINETO %f,%f", coords[0], coords[1]));
                break;
            case PathIterator.SEG_CLOSE:
                System.out.println("SEG_CLOSE");
                break;
            case PathIterator.SEG_MOVETO:
                System.out.println(String.format("SEG_MOVETO %f,%f", coords[0], coords[1]));
                break;
            default:
                System.out.println("*** More complicated than LINETO... Maybe should use FlatteningPathIterator? ***");
                break;
            }
        }
    }
}

Among the other potential positive values of answering questions there, I noticed one today: the process tends to elicit memories of knowledge or talents that I had forgotten that I have. Should be interesting.

I’d figure there’s a one-word description for that since it comprises about 80% of all answers on any given forum.

The basic idea behind the book is that a major problem solving technique that appears in various guises is to transform the problem from one domain to another, solve the transformed problem, then transform the solution back to the original domain. In a pseudo-mathematical manner of speaking: T^-1MT. The author gathered examples from different fields and made some arguments about the generalization. Don’t remember a lot about it, but I’m going to find a copy again and read a bit more…

In searching for the answer, I used
strace -f >trace.txt 2>&1
to try to see what was going on. I found that somehow, something was trying to launch firefox-3.5, which no longer exists (3.5 having taken over as the default version now). Nothing in /etc/ was referring to this… Some searching on the web led me to learn about xdg-open, which calls gnome-open, which uses settings in GConf to figure out how to launch a URL. Launching gconf-editor and finding ‘/desktop/gnome/url-handlers/http’ and ‘/desktop/gnome/url-handlers/https’, I saw that the command for each was ‘firefox-3.5′. Changed those back to ‘firefox’ and everything was cool again.

Now that I see that, I think I used gconf-editor to set those the other way when I first started using firefox-3.5. So it’s sorta my fault, although it wouldn’t be a terrible thing if the install scripts looked for and repaired that sort of error.

This time around, I wanted a bit more of an automated approach. I haven’t seen any great results yet, but here are some that are at least sorta evocative:
“The Miss Rhode Island pageant” < => “The time and rags and polishes”
“federal constitution” < => “failure to discontent”
“that girl with sunbonnet eyes” < => “but only the greatness within”
“college teaching is almost a” < => “glance at the seismological”
“a cut over his left eyebrow” < => “over by the sluice of water”

The approach I took this time was to start with an English corpus (well, a couple, appended, totaling 3M words). For each ‘phrase’ (sequence of consecutive words, really) of between 3 and 6 words, I stick the phrase in a list in a hashmap, where the key is the sorted list of letters used in the phrase. After eating through the whole corpus (which bloats the Python hashmap to about 4GB of RAM), I look for any lists of length longer than one, sort and filter the results to be a little more useful, and spew out the results. Even though the input comes from a nominally grammatical source, there’s still plenty of dumb junk, so it still requires a human to pick out the few good answers, and maybe do some word reordering. And even after that, you end up with what you see above, so, ya know, why bother? Just cuz.

For those who aren’t aware of the term, Wikipedia gives a decent definition, in the “Problems with software” section. I might say it this way: if the world around it changes but your code doesn’t, it’s probably rotting. That violates our deepest wish that software could be written once and left to run forever of its own accord, but it’s simply a fact of life, or at least a good way to accumulate billable hours.

• electric generators
• digital computers
• rockets
• satellites
• radio transmission
• LCD monitors
• video cameras

and, ya know, whatever other infrastructure is needed to effectively support those. When the inevitable question arises about motivation for pursuing these projects, I’ll explain to them that when this is all knit together, everyone in the known world will be able to sit in their homes and watch a bunch of strangers compete to lose the most weight.

The onboard web-based configuration software is pretty lackluster, but it does seem to do the job if you know what you’re doing and/or are curious enough (like, if you want to set up the CIFS parameters for scanning, don’t look under ‘Network Configuration’, and don’t try to find a ‘Scanner Settings’ like the ‘Fax Settings’ and ‘Printer Settings’… You have to find ‘Administrator Settings’ and the subpage ‘FTP/Network Scan Settings’ then ‘FTP/Network Scan Profile’.).

Since it’s all network-based and the onboard computer seems to be pretty smart, I can share it with all my computers easily and with Mac or Windows when I happen to be in those sort of modes.

The hardware is also good; the automatic document feeder is a big reason I got this model, and it seems to be robust and fast. Prints look very nice. I like the fact that it’s a toner system rather than an ink system, because I use my printer so seldom that inks would dry out on me between uses (though I haven’t used an inkjet in about 5 years, maybe they’re better now).

I’m not much for writing comprehensive reviews, but I just wanted to make a note for those who use Linux and were looking at this model. I’ll answer questions should any such person come around…

I love the insider’s view of things. Even if I don’t want to be an insider in a particular field, I really like to immerse myself in their views and language, when I have the time to, rather than sticking to the strictly outsider accounts (popularizations). So a library (especially a university library) is a perfect place for me: it’s mostly full of insider accounts of fields and topics within those fields. If I had to go out and spend $50-$100 per technical book, I wouldn’t be able to frequently dip my nose in a field for a few dozen or few hundred pages and then put it aside again.

I ran across an unexpectedly interesting book in the ISU library today. I did a search for “domain specific language” in the catalog. Since their computing collection is a little slow to catch up to the outside world, they didn’t have any of the several books on domain-specific computer languages published in the last few years. But they did have one on “Domain-specific English”, which turns out to be pretty cool for reasons that I won’t really go into too deeply here. Go find it at your library if you want to know more about that…

There’s a bit in here that was particularly relevant to me:

I remember one winter afternoon, mothers chirping in a corner of the playground as they waited for the bell to announce the schoolday’s end. Their talk focussed on homework – a subject of daily comments – but the conversation sounded more lively than usual. The topic of discussion, and of much stigmatizing, was the reading assignment for that day. Since my own child was in the class, I was aware that the purpose of the assignment had been to encourage children to read for global comprehension and to guess what unfamiliar words could mean. To my surprise, most mothers had missed this point entirely and were indignant. In their opinion, the assignment featured too many difficult words. Some complained about having to consult the dictionary to help clarify the precise meaning of the new words: wasn’t it too early to face such vocabulary? How surprising from an experienced teacher like our maestra!

(And yeah, I know it’s pretty meta to be quoting that in this context.)

I was lucky enough to have parents that would have been among the dissenters in that conversation. They never acted like or told me that some particular text might be ‘too hard’ for me, and they never would have recoiled in shock that some assignment had caused me to use a dictionary. I don’t know that they ever positively subscribed to a pedagogic theory that included the idea of reading for global comprehension and guessing, but the fact that they didn’t discourage it allowed me to develop my own unconscious theory of learning along those lines. If I had to guess, I’d say that children tend to want to explore the world according to those principles, and only discouraging them would stop that short.

Anyway, what was I saying? Oh, yeah: I had fun at the library today. That’s all.