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#Removes all tfs except the one that has 'base_footprint' as child frame id
rosbag filter old.bag new.bag "topic != '/tf' or (len(m.transforms)>0 and m.transforms[0].child_frame_id=='base_footprint')"

#Same as above but limiting other topics to '/odom' and '/scan'
rosbag filter old.bag new.bag "topic == '/odom' or topic == '/scan' or (topic == '/tf' and len(m.transforms)>0 and m.transforms[0].child_frame_id=='imu_link')"

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#Convert the format of one image
convert source.pgm target.png

#Convert all images format of one type into another
# e.g. png is the target format
# e.g. all pgm images starting with "source" are converted
mogrify -format png source*.pgm

#Convert multiple images to one animated image
# e.g. takes all pgm images in the folder to create one animated gif. Verify that the images are numbered in ascending order. 

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nmap -p 25 -sC yourDomain.com

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# This can be quite useful to run some process on the server, 
# as it will not listen to the hangup signal of the terminal 
# and will not terminate the process, if you close the terminal.
# In addition all output is appended in the log file
nohup /usr/bin/python3.4 /abspath/someFile.py 2>&1 | /usr/bin/tee -a /abspath/log.txt &

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# Quickly create an android app for IoT :
https://www.blynk.cc/

#ROS stack and library for roomba and create:
https://github.com/AutonomyLab/create_autonomy
https://github.com/AutonomyLab/libcreate/blob/master/include/create/types.h

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# Replace OLD with the string you want to replace, and NEW with the string you want to insert

find ./ -type f -exec sed -i -e 's/OLD:/NEW:/g' {} \;

grep -rl 'OLD' .  | xargs sed -i 's/OLD/NEW/g'

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#Example:

#get some info with:
udevadm info -a -n /dev/ttyUSB0 | grep serial
udevadm info -a -n /dev/ttyUSB0 | grep idProduct
udevadm info -a -n /dev/ttyUSB0 | grep idVendor
#or
 udevadm info -a -n /dev/ttyUSB0 | grep -E 'idVendor|idProduct|serial' 

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#!/usr/bin/env python
import paho.mqtt.client as mqtt
import RPi.GPIO as GPIO
import time
import signal
TOPIC_1= "lab_switch"
HOST="localhost"
USER="openhab"
class MQTTGPIO():
    def __init__(self):

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+ Plugin SD card that contains the Raspbian OS into your computer
+ Find the partition that is called "boot"
+ Create a file there called ssh

REMARK: Only works for raspbian!

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#!/bin/bash
# Splits the PDF in single pages PDFs which are saved in a subfolder called extracted and the page name. 
# If the pages does already exist, it will increment the page number by one, until the filename is not occupied.

#sudo apt-get install pdftk
#chmod +x split_pdf.bash
#./split_pdf.bash source.pdf

PDFFILE=$1
echo "File: "$PDFFILE