Try   HackMD

Linux

User:

  1. Regular user (only has access in their home directory only)
  2. Root user or Super user (Admin)

  • $ : Regular User

  • (#) : Sudo user/Super user

  • Absolute Path : cd/bin/fo1

  • Relative Path : cd fo2

Basic Linux commands

  • pwd : print working directory

  • ls : Lists all files and directories in the present working directory

  • ls-R : Lists files in sub-directories as well

  • ls-a : Lists hidden files as well

  • ls-al : Lists files and directories with detailed information like permissions,size, owner, etc.

  • ls -lart : list files with read/write acess

  • cd or cd ~ : Navigate to HOME directory

  • cd .. : Move one level up

  • cd : To change to a particular directory

  • cd / : Move to the root directory

  • cat > filename : Creates a new file

  • cat filename : Displays the file content

  • cat file1 file2 > file3 : Joins two files (file1, file2) and stores the output in a new file (file3)

  • mv file "new file path" : Moves the files to the new location

  • mv filename new_file_name : Renames the file to a new filename

  • sudo : Allows regular users to run programs with the security privileges of the superuser or root

  • rm filename : Deletes a file

  • man : Gives help information on a command

  • history : Gives a list of all past commands typed in the current terminal session

  • clear : Clears the terminal

  • mkdir directoryname : Creates a new directory in the present working directory or a at the specified path

  • rmdir : Deletes a directory

  • mv : Renames a directory

  • pr -x : Divides the file into x columns

  • pr -h : Assigns a header to the file

  • pr -n : Denotes the file with Line Numbers

  • lp -nc , lpr c : Prints “c” copies of the File

  • lp-d lp-P : Specifies name of the printer

  • apt update : Command used to check update

  • apt upgrade : command for installing update

  • touch harry.txt : create harry.txt file

File Permission commands

  • ls-l : to show file type and access permission
  • r : read permission
  • w : write permission
  • x : execute permission
  • -= : no permission
  • Chown user : For changing the ownership of a file/directory
  • Chown user:group filename : change the user as well as group for a file or directory

Environment Variables command

  • echo $VARIABLE : To display value of a variable
  • env : Displays all environment variables
  • VARIABLE_NAME= variable_value : Create a new variable
  • Unset : Remove a variable
  • export Variable=value : To set value of an environment variable

User management commands of linux

  • sudo adduser username : To add a new user
  • sudo passwd -l 'username' : To change the password of a user
  • sudo userdel -r 'username' : To remove a newly created user
  • sudo usermod -a -G GROUPNAME USERNAME : To add a user to a group
  • sudo deluser USER GROUPNAME : To remove a user from a group
  • finger : Shows information of all the users logged in
  • finger username : Gives information of a particular user

Networking command

  • SSH username@ip-address or hostname : login into a remote Linux machine using SSH
  • Ping hostname="" or ="" : To ping and Analyzing network and host connections
  • dir : Display files in the current directory of a remote computer
  • cd "dirname" : change directory to “dirname” on a remote computer
  • put file : upload ‘file’ from local to remote computer
  • get file : Download ‘file’ from remote to local computer
  • quit : Logout

Process command

  • bg : To send a process to the background
  • fg : To run a stopped process in the foreground
  • top : Details on all Active Processes
  • ps : Give the status of processes running for a user
  • ps PID : Gives the status of a particular process
  • pidof : Gives the Process ID (PID) of a process
  • kill PID : Kills a process
  • nice : Starts a process with a given priority
  • renice : Changes priority of an already running process
  • df : Gives free hard disk space on your system
  • free : Gives free RAM on your system

VI Editing Commands

  • i : Insert at cursor (goes into insert mode)
  • a : Write after cursor (goes into insert mode)
  • A : Write at the end of line (goes into insert mode)
  • ESC : Terminate insert mode
  • u : Undo last change
  • U : Undo all changes to the entire line
  • o : Open a new line (goes into insert mode)
  • dd : Delete line
  • 3dd : Delete 3 lines
  • D : Delete contents of line after the cursor
  • C : Delete contents of a line after the cursor and insert new text. Press ESC key to end insertion.
  • dw : Delete word
  • 4dw : Delete 4 words
  • cw : Change word
  • x : Delete character at the cursor
  • r : Replace character
  • R : Overwrite characters from cursor onward
  • s : Substitute one character under cursor continue to insert
  • S : Substitute entire line and begin to insert at the beginning of the line
  • ~ : Change case of individual character

chmod : Change file mode

  • Go to chmod calculator, select your permission in different segment like (Owner, Group, other

  • Copy that number/ or use this number to change mode of a file.

  • chmod 732 1.tx

vim : is a edtior

  • apt install vim
  • vim harry.txt - harry.txt file open in vim editor.
  • i - to go to insert mode to write.
  • esc - to escape from insert mode. then
  • colon(:) - if you want to exit without save write q! or if you want to save and exit then write wq and enter.
Last changed by 
 
UPENDRA KUMAR
0
111

Read more

Region Based Convolutional Neural Networks

Article on Selective Search Algorithm: https://www.geeksforgeeks.org/selective-search-for-object-detection-r-cnn/ RCNN:

Nov 7, 2022
Mask RCNN

Introduction Mask R-CNN is a masterpiece of He Kaiming God in 2017. It performs instance segmentation while performing target detection, and has achieved excellent results. It has won the COCO 2016 championship without any tricks. The design of its network is also relatively simple. On the basis of Faster R-CNN, a branch is added to the original two branches (classification + coordinate regression) for semantic segmentation , as shown in the following figure Mask R-CNN detailed Introduction So why does this network have such good results, and what are the network details? The following are introduced one by one in detail. Before introducing Mask R-CNN, first understand what is segmentation, because Mask R-CNN does this, so this must be figured out first, see the following figure, which mainly introduces several different segmentation, of which Mask RCNN does Among theminstance segmentation. Semantic segmentation: classify pixel by pixel in an image.

Jan 25, 2022
Comparison of YOLO1, YOLO2, and YOLO3

YOLO1 1.The main ideas of target detection Unlike the RCNN series, YOLO treats target detection as a regression problem, and directly uses a network for classification and box regression. The specific method is: divide the image into S * S grids, and each grid predicts the positions (x, y, w, h) of B bboxes, confidence (confidence is the intersection ratio), and class probability. The output dimension is S * S * (B * 5 + C), and C is the number of categories. No matter how many boxes are contained in the grid, each grid only predicts a set of class probabilities. During the test, the conditional class probability and the confidence of the prediction box are multiplied to indicate that each box contains the confidence of a certain type of object. This score can represent the category probability and prediction accuracy of the box at the same time. 2. Overall network structure The basic network model is GoogLe Net, but instead of using its inception module, it uses 1 * 1 and 3 * 3 convolutional layers alternately.

Jan 3, 2022
Inception (Also Known as GoogleNet)

Also known as GoogLeNet , it is a 22-layer network that won the 2014 ILSVRC Championship. The original intention of the design is to expand the width and depth on its basis . which is designed motives derived from improving the performance of the depth of the network generally can increase the size of the network and increase the size of the data set to increase, but at the same time cause the network parameters and easily fit through excessive , computing resources inefficient and The production of high-quality data sets is an expensive issue. Its design philosophy is to change the full connection to a sparse architecture and try to change it to a sparse architecture inside the convolution. The main idea is to design an inception module and increase the depth and width of the network by continuously copying these inception modules , but GooLeNet mainly extends these inception modules in depth.

Nov 11, 2021
Read more from UPENDRA KUMAR
Published on HackMD