09 March 2021

670. Issues with the RSC latex template -- text shifted on debian buster

Using the RSC latex template -- last updated 2016 -- works fine on debian stretch. However, on debian buster the text is screwed up on all pages except for the first one: the header is way too big, and the text runs off the page at the bottom.

After having spent a lot of time looking at log files, comparing installed packages on different machines, and generally not making any progress, I finally found this:

https://tex.stackexchange.com/questions/495662/rsc-template-fancyhdr-doesnt-respond-well

which links to 

https://tex.stackexchange.com/questions/491859/what-has-changed-in-latex-that-means-the-rsc-template-no-longer-works#comment1242180_491859

Since links die occasionally I'll summarize it here (I DID NOT COME UP WITH THIS SOLUTION):

Fancyhdr has been updated between stretch and buster, and while the maintainers at Overleaf have fixed the RSC template and notified RSC of the changes necessary, the current (8/3/2021) version of the template is still faulty.

To fix you can either 

1) edit the .tex file template itself

a) Comment out 

\fancyhead[C]{\includegraphics[width=18.5cm]{head_foot/header_bar}}
\fancyhead[L]{\hspace{0cm}\vspace{1.5cm}\includegraphics[height=30pt]{head_foot/PCCP}}
\fancyhead[R]{\hspace{0cm}\vspace{1.7cm}\includegraphics[height=55pt]{head_foot/RSC_LOGO_CMYK}}

b) find vspace{3cm} after \twocolumn[..] and add

{\includegraphics[height=30pt]{head_foot/journal_name}\hfill%
 \raisebox{0pt}[0pt][0pt]{\includegraphics[height=55pt]{head_foot/RSC_LOGO_CMYK}}%
 \\[1ex]%
 \includegraphics[width=18.5cm]{head_foot/header_bar}}\par

right before it.

Then change \vspace{3cm} to \vspace{1em}

or 

2) add some extra .sty files to the folder with your .tex file. Those files are:
balancy.sty, caption.sty, caption3.sty, fancyhdr.sty, mchem.sty and secsty.sty

They can be had from https://github.com/bardsoftware/template-RSC/tree/master/Paper

07 December 2020

669. Checking how many students attended a zoom lecture, afterwards

 This is an easy one, but you need to know that 1) the option is there and 2) where to look.

Go to the web-interface to zoom at your institution, and click on log in:


Now that you're in, go to to Reports:


Then go to Usage:



Now, search for the time period that you're interested in:


And click on the number of attendees. Note that if someone gets disconnected, and then reconnect, they're counted twice, so this is not the value you want to use:



Instead, make sure to click "Show unique users" to see how many students actually attended. You can also export it as a csv file which is probably a good idea since you'll need to count by hand otherwise:



That's it.



30 October 2020

668. Controlling the fan speed of an Nvidia card when you're using the nouveau driver and no xorg.conf

 My old GT210 has served me well, but I've had a few odd freezes recently, coupled with weird graphics behaviour. It's a pity, since it's a nice, silent fan-less graphics card from way back when: https://www.gigabyte.com/Graphics-Card/GV-N210SL-1GI#ov

Although some of it may be due to switching back and forth between VGA and HDMI output (between an old HP 19'' and my new fancy xp pen display) I ripped it out and replaced it with an almost as ancient GT 520 (https://www.gigabyte.com/Graphics-Card/GV-N520OC-1GI#ov)

The fan isn't loud, but it's there, and it's distracting since I'm working in a home environment (Corona!).

Looking online I found these posts:
http://floppym.blogspot.com/2013/07/fan-control-with-nouveau.html
https://forums.opensuse.org/showthread.php/501517-OS-13-1-Driver-quot-nouveau-quot-Unable-to-command-fan-speed-Nvidia-6800-GS
https://www.kernel.org/doc/Documentation/thermal/nouveau_thermal

So, first to check if fan control is possible:

me@indium:~$ find /sys -name pwm1_enable
find: ‘/sys/kernel/debug’: Permission denied
/sys/devices/platform/it87.2624/hwmon/hwmon2/pwm1_enable
/sys/devices/platform/it87.2656/hwmon/hwmon3/pwm1_enable
/sys/devices/pci0000:00/0000:00:03.0/0000:05:00.0/hwmon/hwmon0/pwm1_enable
me@indium:~$ readlink /sys/devices/pci0000:00/0000:00:03.0/0000:05:00.0/driver
../../../../bus/pci/drivers/nouveau

Good, and we got the hwmon number -- 0. 

I then created a script called gpufan.sh:

sudo sh -c "echo 1 > /sys/class/hwmon/hwmon0/pwm1_enable"
sudo sh -c "echo 35 > /sys/class/hwmon/hwmon0/pwm1_min"
sudo sh -c "echo 45 > /sys/class/hwmon/hwmon0/pwm1"

I set the min% to 35 -- it used to be 65. And I tested my way to 45% as a good compromise between noise and temperature. By default the fan speed was >4,000 rpm. Output from sensors now:

nouveau-pci-0500
Adapter: PCI adapter
GPU core:     +0.90 V  (min =  +0.90 V, max =  +1.11 V)
fan1:        2790 RPM
temp1:        +34.0°C  (high = +95.0°C, hyst =  +3.0°C)
                       (crit = +105.0°C, hyst =  +5.0°C)
                       (emerg = +135.0°C, hyst =  +5.0°C)