KbDemo not working on Octave+Ubuntu

Hardware
1

Hi,
neither KbDemo nor KbQueueDemo appears to work properly for on my recent PTB+Octave installation (screen commands seem to work fine).

When I type KbDemo, nothing happens, until I press CTRL+C
Only after that, the output appears
1 of 4. Testing KbCheck and KbName: press a key to see its number.
Press the escape key to proceed to the next demo.
You pressed key 37 which is Return
You pressed key 37 which is Return
You pressed key 37 which is Return
You pressed key 37 which is Return
You pressed key 37 which is Return
You pressed key 37 which is Return
You pressed key 37 which is Return
You pressed key 37 which is Return
You pressed key 37 which is Return
You pressed key 37 which is Return
You pressed key 37 which is Return
You pressed key 37 which is Return
You pressed key 38 which is LeftControl

PsychHID-INFO: CTRL+C DETECTED! Trying to reenable keyboard input to console. [(nil)]

Not sure whether this is a bug, a harware issue, or an isntallation issue (I installed ptb through apt-get install and ran all general and linux-related post-install routines)

System/version info below:

PsychtoolboxVersion

ans = 3.0.14 - Flavor: Debian package - psychtoolbox-3 (3.0.14.20170103+git6-g605ff5c.dfsg1-1build1)
For more info visit:
http://neuro.debian.net/pkgs/octave-psychtoolbox-3.html

Octave version 4.2.2

Linux Ubuntu 18.04.4

New DELL XPS13 laptop

2

That’s strange. Ubuntu 18.04.4 + Octave 4.2.2 is my main development+test system, and here everything works fine.

Your PTB 3.0.14 is old and from Ubuntu itself, not from NeuroDebian. Can you upgrade to the latest 3.0.16 PTB from NeuroDebian and retest?

http://neuro.debian.net/install_pkg.html?p=octave-psychtoolbox-3

Maybe i fixed something somewhere throughout the over 2 years since 3.0.14.

Hm. But what i think it is is output paging. It is on by default on older Octave, but off on Matlab by default. It is the one thing i always change first after installing octave on a machine:

Type: more off
Then retry.

If this helps, you can create an ~/.octaverc config file with a call to that function, e.g., in a terminal:

echo “more off;” >> ~/.octaverc

-mario

3

Hi Mario,
it was indeed the output paging! I used Octave before, but don’t remember having this problem.
Although the PTB version was not an issue, I upgraded :wink:

Cheers!
Natalia