Line-Count-Complexity-OS

Counting number of lines in a file using Shell Script and determining its time complexity.

This mini-project was developed for the partial fulfilment of the 2nd year, 4th semester of Bachelor of Technology in Operating System : CSD-222 by following students:-

• Avinal Kumar
• Harsimranjeet Singh Saini
• Pooja Nehra

Actual Project Statement

Using a Shell Script define a function count_lines that counts the number of lines in the file provided asargument. Inside the functionthe value of the argument is retrieved by assessing the varible $1.

Discuss the complexity of the code and propose your amendments.

Project Resources

• Project Report

Get Started with the project

1. Prerequisite
   • Any linux distribution because its a bash based project
   • C++ compiler - gcc or g++ with make utility
   • MatLab to plot the curve
2. Clone this repository and run make command

   git clone https://github.com/avinal/Line-Count-Complexity-OS
   cd Line-Count-Complexity-OS/src
   make
   ./complexity_test
   

3. This will generate three files timedur.txt, testfile.txt and comparefile.txt. We can now use MatLab to plot the time complexity curve. You can run the above program multiple times with differnt output filename to get better average result.
4. Open MatLab and import all timedur.txt and complexity_curve.m files. Currently the matlab function uses two runs of the program you can modify it to average as many runs you want.
5. Run complexity_curve in MatLab command prompt. The curve will be plotted with the line fitting.

Analysis

In our experiment we used a text file upto 1 Million lines and tracking the time taken by the script per 1000 line increment. Each line is a same random string of 1000 characters. Here is our result.

As we can see the curve fitting is linear. However at many point result is far from being linear but for the average part we can assume it be linear.

We can improve the accuracy by running the program multiple time and plot the average result.

We can infer that the function runs in O(n) time.