Fibonacci Search Visualizer using PyQt5

In this article we will see how we can make a PyQt5 application which will visualize the exponential search algorithm.

Fibonacci search technique is a method of searching a sorted array using a divide and conquer algorithm that narrows down possible locations with the aid of Fibonacci numbers.[1] Compared to binary search where the sorted array is divided into two equal-sized parts, one of which is examined further, Fibonacci search divides the array into two parts that have sizes that are consecutive Fibonacci numbers.

GUI implementation steps :
1. Create a list of label according to the given list of numbers
2. Set their text, border, color and geometry with respective gap from each other
3. Each label height should be proportional to the value of each number
4. Create a start and pause push button to start the searching and pause the searching
5. Create a result label to show the searching status

Back end implementation steps :
1. Create label list corresponding to the given numbers
2. Create variable for the index used by Fibonacci search and flag for searching and flag for searching    minimum Fibonacci number and for searching value after getting the Fibonacci number
3. Add action to the push button their action should change the flag status i.e start action should make    flag true and pause action should make flag false
4. Create timer object which calls a method after every specific time
5. Inside the timer method check for the flag is flag is true begin the search of Fibonacci number
6. After finding the fibonacci number find the given number within the range
7. Show the result

Below is the implementation





# importing libraries
from PyQt5.QtWidgets import * 
from PyQt5 import QtCore, QtGui
from PyQt5.QtGui import * 
from PyQt5.QtCore import * 
import sys
class Window(QMainWindow):
    # list of numbers
    number = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15]
    # desired list
    desired = 14
    def __init__(self):
        # setting title
        self.setWindowTitle("Fibonacci Search")
        # setting geometry
        self.setGeometry(100, 100, 600, 400)
        # calling method
        # showing all the widgets
    # method for widgets
    def UiComponents(self):
        # start flag
        self.start = False
        # divide flag
        self.divide = False
        self.fib_search = True
        # list to hold labels
        self.label_list = []
        # fibonacci numbers
        self.fib1 = 1
        self.fib2 = 0
        self.fib = self.fib1 + self.fib2
        self.offset = -1
        # local counter
        c = 0
        # iterating list of numbers
        for i in self.number:
            # creating label for each number
            label = QLabel(str(i), self)
            # adding background color and border
            label.setStyleSheet("border : 1px solid black;
                                 background : white;")
            # aligning the text
            # setting geometry using local counter
            # first parameter is distance from left
            # and second is distance from top
            # third is width and forth is height
            label.setGeometry(50 + c * 30, 50, 20, i * 10 + 10)
            # adding label to the label list
            # incrementing local counter
            c = c + 1
        # creating push button to start the search
        self.search_button = QPushButton("Start Search", self)
        # setting geometry of the button
        self.search_button.setGeometry(100, 270, 100, 30)
        # adding action to the search button
        # creating push button to pause the search
        pause_button = QPushButton("Pause", self)
        # setting geometry of the button
        pause_button.setGeometry(100, 320, 100, 30)
        # adding action to the search button
        # creating label to show the result
        self.result = QLabel("To search : " + str(self.desired), self)
        # setting geometry
        self.result.setGeometry(320, 280, 250, 40)
        # setting style sheet
        self.result.setStyleSheet("border : 3px solid black;")
        # adding font
        self.result.setFont(QFont('Times', 10))
        # setting alignment
        # creating a timer object
        timer = QTimer(self)
        # adding action to timer
        # update the timer every 300 millisecond
    # method called by timer
    def showTime(self):
        # checking if flag is true
        if self.start:
            # search fibonacci number
            if self.fib_search:
                # searching for the Fibonacci number greater
                # then the desired number
                if self.fib < len(self.number):
                    self.fib2 = self.fib1
                    self.fib1 = self.fib
                    self.fib = self.fib2 + self.fib1
                    self.result.setText("Searching Fibonacci number >=" + 
                # start divide search
                    self.result.setText("Fibonacci found, searching number")
                    self.fib_search = False
                    self.divide = True
            # start devide search
            if self.divide:
                if self.fib <= 1:
                    self.result.setText("Not found")
                    self.start = False
                i = min(self.offset + self.fib2, len(self.number) - 1)
                self.label_list[i].setStyleSheet("border : 1px solid black;"
                                                 "background-color : grey")
                # If desired is greater than the value at
                # index fib2, cut the subarray array
                # from offset to i
                if (self.number[i] < self.desired):
                    self.fib = self.fib1
                    self.fib1 = self.fib2
                    self.fib2 = self.fib - self.fib1
                    self.offset = i
                # If desired is greater than the value at
                # index fib2, cut the subarray
                # after i + 1
                elif (self.number[i] > self.desired):
                    self.fib = self.fib2
                    self.fib1 = self.fib1 - self.fib2
                    self.fib2 = self.fib - self.fib1
                # element found. show result and stop search
                    self.result.setText("Found at : " + str(i))
                                 "border : 2px solid green;"
                                 "background-color : lightgreen;")
                    self.start = False
    # method called by search button
    def search_action(self):
        # making flag true
        self.start = True
        # showing text in result label
        self.result.setText("Started searching...")
    # method called by pause button
    def pause_action(self):
        # making flag false
        self.start = False
        # showing text in result label
# create pyqt5 app
App = QApplication(sys.argv)
# create the instance of our Window
window = Window()
# start the app


Output :

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