ImageMagick: montage images into one

montage -label '%f' -geometry +4+4 -pointsize 20 -tile 4x6 *.tiff mtg.jpg

ImageMagick: Flatten image results in white image

Instead of -flatten option try using -layers trim-bounds

UFW: forward trafic on a port 8333 to different computer/ip and back

Full node is running on: ip_full_node Redirection is done on server: ip_of_uwf_server *nat
:PREROUTING ACCEPT [0:0]
:POSTROUTING ACCEPT [0:0]
-F
-A PREROUTING -i eth0 -p tcp --dport 8333 -j DNAT --to-destination ip_full_node:8333
-A POSTROUTING -p tcp -d ip_full_node --dport 8333 -j SNAT --to-source ip_of_uwf_server
-A POSTROUTING -s 10.8.0.0/8 -o eth0 -j MASQUERADE
COMMIT
Based on: https://serverfault.com/a/586553

ImageMagick: remove alpha channel from tiff images

mogrify -flatten -alpha off *.tiff

HDMI audio output in Arch for KDE

aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: PCH [HDA Intel PCH], device 0: ALC898 Analog [ALC898 Analog]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 0: PCH [HDA Intel PCH], device 1: ALC898 Digital [ALC898 Digital]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 1: NVidia [HDA NVidia], device 3: HDMI 0 [HDMI 0]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 1: NVidia [HDA NVidia], device 7: HDMI 1 [HDMI 1]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 1: NVidia [HDA NVidia], device 8: HDMI 2 [HDMI 2]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 1: NVidia [HDA NVidia], device 9: HDMI 3 [HDMI 3]
  Subdevices: 1/1
  Subdevice #0: subdevice #0


aplay -D plughw:1,7 /usr/share/sounds/alsa/Front_Right.wav

VirtualBox: resize disk in linux

Resize to 350GB using VirtualBox 5.18: VBoxManage modifyhd "/home/myhome/VirtualBox VMs/arc/arc.vdi" --resize 350000 Full path to virtual disk (e.g., arc.vdi) is important. Without the full path, the following error occurs: VBoxManage: error: Cannot register the hard disk '/home/myhome/VirtualBox VMs/arc/./arc.vdi' {54199b9e-0a91-4d84-a7d0-fe2b47ed8f47} because a hard disk '/home/myhome/VirtualBox VMs/arc/arc.vdi' with UUID {54199b9e-0a91-4d84-a7d0-fe2b47ed8f47} already exists
VBoxManage: error: Details: code NS_ERROR_INVALID_ARG (0x80070057), component VirtualBoxWrap, interface IVirtualBox, callee nsISupports
VBoxManage: error: Context: "OpenMedium(Bstr(pszFilenameOrUuid).raw(), enmDevType, enmAccessMode, fForceNewUuidOnOpen, pMedium.asOutParam())" at line 179 of file


Linux: mkdir and cd in one command

mkcd () {
case "$1" in */..|*/../) cd -- "$1";; # that doesn't make any sense unless the directory already exists
/*/../*) (cd "${1%/../*}/.." && mkdir -p "./${1##*/../}") && cd -- "$1";;
/*) mkdir -p "$1" && cd "$1";;
*/../*) (cd "./${1%/../*}/.." && mkdir -p "./${1##*/../}") && cd "./$1";;
../*) (cd .. && mkdir -p "${1#.}") && cd "$1";;
*) mkdir -p "./$1" && cd "./$1";;
esac
}

From: http://unix.stackexchange.com/a/9124/90216

Windows 8.1: start chrome in new session and monitor

"C:\Program Files (x86)\Google\Chrome\Application\chrome.exe" --user-data-dir=c:/monitor1

Linux SPSS 24: R 3.2 was not found in this location.

When installing R essentials for linux it is unclear how to specify R path. Without this, the following error occures:

 R 3.2 was not found in this location. Please click Previous to select a different location, or install R 3.2 on this computer and run this installation again.

For me the answer was to proved a path where `lib64` of the R package is located, not where the R binary is as show on this screenshot

In the screenshot /opt/r32 is my installation folder (I compiled version 3.2.2 it myself from source). The binary R is in /opt/r32/bin. This will not work. The path must be to R folder inside lib64 folder.

Chrome through ssh tunel

ssh -ND 1080 user@remote_server_ip -p 2222 google-chrome-stable --proxy-server="socks5://localhost:1080" --proxy-bypass-list="localhost;127.0.0.1"