The symptom was that in an Emacs buffer, after hitting Ctrl and the spacebar (C-space) and then moving the cursor, I was expecting the text in between (between mark and point) to be highlighted (indicating an active region), but the region was not highlighted and not active. Accordingly, then doing a replace-string and expecting it to replace text in the region that is “normally” (in Emacs 23) highlighted did not replace anything. (I was, however, able to cut and paste (kill and yank) the same region. In Emacs-speak, the region was not active. Another symptom: after M-x replace-string where I normally see “Replace string in region” in the minibuffer, it now only said “Replace string”.

The solution:

M-x transient-mark-mode

to enable transient-mark-mode and get the expected behaviour (this command toggles it on and off).

sudo aptitude install likewise-open5

Connect:

sudo domainjoin-cli join kclad.ds.kcl.ac.uk LOGIN

Reboot.
Add the line winbind use default domain = yes to the file /etc/samba/lwiauthd.conf
Reboot.
Check if you are connected:

sudo domainjoin-cli query

I now seem to be connected whenever I am on the KCL network.
Leave:

sudo domainjoin-cli leave

(I don’t explicitly leave. It disconnects when I disconnect from the network.)

hp-probe -bnet | grep printer0

This returns lines that contain a URI like this

hp:/net/HP_LaserJet_P3005?ip=159.92.99.39

Copy that and go back to the GUI where you paste it under “Enter device URI”

invalid argument to unary operator

It happened when I was specifying custom labels with scale_y_continuous but it turns out this was irrelevant and it hinged on a line break. It turnsout (at least when stepping through the code with ESS in Emacs using C-c C-c, bound to ess-eval-function-or-paragraph-and-step, you need to have the + of tying different ggplot bits together on the end of the preceding line.

This won’t work:

ggplot(longdata, aes(x=x, y = y))
+ geom_jitter(alpha = 0.6)

This will:

ggplot(longdata, aes(x=x, y = y)) +
geom_jitter(alpha = 0.6)

(Or, put it all on one line).

I haven’t tried it, but it looks like it could be a nice way to do some speedy PHP-based questionnaires.

sed -i 's/[^,]*,//' file.csv

Note the [^,]* bit, which matches everything that is not a comma. Don’t use .*, because this will greedily match commas, too. (Usually, cut is useful for these sort of things, but cut cannot readily replace the file in place.)

gconf-editor

and change the setting desktop → gnome → interface → gtk_key_theme from “Default” to “Emacs”.

If you show us your data/code/output as has been requested, then we may be able to tell which it is. Without that information you are expecting either R or the members of the list to read your mind. I keep making notes to my future self to use the timetravel package (not written yet, that’s why I need my future self to use it) to send a copy of the esp package (also not written yet) back in time to me so I can use it for situations like this. But so far that has not worked (maybe my future self is even more lazy than my present self, or my near future self does something to offend my far future self enough that he is unwilling to do this small favor for my current past self, darn, either way means I should probably do better on the diet/exercise).

Time for lunch.