Function Tabulator

A C++ console application that tabulates a piecewise-defined function over the interval [a, b] with a step size of h using Formula. The project includes source code, UML and Use Case diagrams, a flowchart, usage scenarios, and reports for laboratory assignments 1 and 2.

Author

• Student: Sokurenko David
• University: National Technical University «Kharkiv Polytechnic Institute»
• Group: KN-226e
• Year: 2026

Formula

$$y = \begin{cases} 12x - \displaystyle\sum_{i=2}^{n+1}(i - x^2), & x < 0, \\\ \displaystyle\sum_{i=0}^{n}\prod_{j=1}^{n-1} \frac{i+j}{x^2} - 5x, & x \geq 0. \end{cases}$$

Input data

Parameter	Description	Requirement
a	Starting value of x	Number
b	End value of x	Number, b ≥ a
h	Step size	Number, h > 0
n	Loops limit	Integer, 2 ≤ n ≤ 10000

The value x = 0 is not calculated (division by zero); an error message is written to the results file for it.

Main Menu

1. Input data (from keyboard or file)
2. Calculate result
3. Exit

When entering data via the keyboard, the letter q cancels the input and returns you to the main menu.

Input from file

The file must be located in the same folder as the program and contain 4 numbers, each on a new line: a, b, h, n. Example: input.txt.

Results

A table of x and y values ​​is displayed in the console (for a very large number of results showing the first and last steps, as well as every 1000th step). All results are automatically saved to a file results.txt.

Example of program work

Keyboard input

File input

Diagrams and Modeling

Lab №1

Use Case Diagram

Activity Diagram

Lab №2

Flowchart (screen transition diagram)

Use cases: docs/use_case_scenarios.md

Reports

• Lab. №1
• Lab. №2

Assembly and startup

The program uses Windows.h, so it runs on Windows (Visual Studio or MinGW):

g++ src/main.cpp -o tabulator.exe
tabulator.exe

Technologies and Tools

C++ (Visual Studio), Visual Paradigm