In this article we will see how we can make a PyQt5 application which will visualize the Exponential search algorithm. Exponential search can also be used to search in bounded lists. Exponential search can even out-perform more traditional searches for bounded lists, such as binary search, when the element being searched for is near the beginning of the array. This is because exponential search will run in O(log i) time, where i is the index of the element being searched for in the list, whereas binary search would run in O(log n) time, where n is the number of elements in the list. 
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 the 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 exponential search and other variable used by binary search index and flag for searching and flag for binary and exponential search. 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 exponential search algorithm 6. Check if value lies within the range if not show output as not found else continue 7. Start finding value at index if found stop the search and show result else double the index value 8. Find the range in which value would be and start binary search and set the lower and upper value of binary search 9. Show result with the help of binary search
Below is the implementationÂ
Python3
# importing librariesfrom PyQt5.QtWidgets import *from PyQt5 import QtCore, QtGuifrom PyQt5.QtGui import *from PyQt5.QtCore import *import sysÂ
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class Window(QMainWindow):    # list of numbers    number = [1, 2, 3, 4, 5, 6, 7, 8, 9,                 10, 11, 12, 13, 14, 15]Â
    def __init__(self):        super().__init__()Â
        # setting title        self.setWindowTitle("Exponential Search")Â
        # setting geometry        self.setGeometry(100, 100, 600, 400)Â
        # calling method        self.UiComponents()Â
        # showing all the widgets        self.show()Â
    # method for widgets    def UiComponents(self):Â
        # start flag        self.start = False        self.binary = False        self.expo = TrueÂ
        # list to hold labels        self.label_list = []Â
        # desired value        self.desired = 8Â
        # Exponential Search variable        self.index = 1Â
        # binary search variable        self.first = 0        self.last = len(self.number) - 1        self.mid = 0Â
        # local counter        c = 0Â
        # iterating list of numbers        for i in self.number:            # creating label for each number            label = QLabel(str(i), self)Â
            # adding background color and border            label.setStyleSheet("border : 1px solid black;                                  background : white;")Â
            # aligning the text            label.setAlignment(Qt.AlignTop)Â
            # setting geometry using local counter            # first parameter is distance from left            # and second is distance from top            # third is width and fourth is height            label.setGeometry(50 + c * 30, 50, 20, i * 10 + 10)Â
            # adding label to the label list            self.label_list.append(label)Â
            # incrementing local counter            c = c + 1Â
        # creating push button to start the search        self.search_button = QPushButton("Start Search", self)Â
        # setting geometry of the button        self.search_button.setGeometry(100, 270, 100, 30)Â
        # adding action to the search button        self.search_button.clicked.connect(self.search_action)Â
        # creating push button to pause the search        pause_button = QPushButton("Pause", self)Â
        # setting geometry of the button        pause_button.setGeometry(100, 320, 100, 30)Â
        # adding action to the search button        pause_button.clicked.connect(self.pause_action)Â
        # creating label to show the result        self.result = QLabel("To search : " + str(self.desired), self)Â
        # setting geometry        self.result.setGeometry(350, 280, 200, 40)Â
        # setting style sheet        self.result.setStyleSheet("border : 3px solid black;")Â
        # adding font        self.result.setFont(QFont('Times', 10))Â
        # setting alignment        self.result.setAlignment(Qt.AlignCenter)Â
        # creating a timer object        timer = QTimer(self)Â
        # adding action to timer        timer.timeout.connect(self.showTime)Â
        # update the timer every 300 millisecond        timer.start(300)Â
    # method called by timer    def showTime(self):Â
        # checking if flag is true        if self.start:Â
            # Exponential Search            if self.expo:Â
                # if equal for index value 0                if self.number[0] == self.desired:                    # stop the searching                    self.start = FalseÂ
                    # show the result and make the label green                    self.result.setText("Found at index : 0" )                    self.label_list[self.index].setStyleSheet(                                    "border : 2px solid green;"                                    "background-color : lightgreen")Â
                # if not equal                else:                    # make the label grey                    self.label_list[0].setStyleSheet(                              "border : 1px solid black;"                              "background-color : grey")Â
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                # double the value of index                self.index = self.index * 2Â
                # temporary stores index                temp = self.indexÂ
                # checking if index is greater then the len of list                if self.index >= len(self.number):Â
                    # update the index                    self.index = len(self.number) - 1Â
                    # start binary search                    self.expo = False                    self.binary = TrueÂ
                    # set variable of binary search                    self.first = temp//2                    self.last = self.indexÂ
                # if desired value is smaller                if self.desired < self.number[self.index]:Â
                    # start binary search                    self.expo = False                    self.binary = TrueÂ
                    # set binary search variables                    self.first = temp//2                    self.last = self.indexÂ
                # if number is equal to the index value                if self.number[self.index] == self.desired:Â
                    # stop the search                    self.start = FalseÂ
                    # show result and make label color green                    self.result.setText("Found at index : " + str(self.index))                    self.label_list[self.index].setStyleSheet(                                    "border : 2px solid green;"                                    "background-color : lightgreen")Â
                # if not equal                else:                    # make label color grey                    self.label_list[self.index].setStyleSheet(                                    "border : 1px solid black;"                                    "background-color : grey")Â
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            # binary search            if self.binary:                # implementing binary search                # finding mid index                self.mid = (self.first + self.last) // 2Â
                # if first index become greater than last index                if self.first > self.last:                    # make start flag false                    self.start = False                    # show output as not found                    self.result.setText("Not Found")Â
                # if mid value is equal to the desired value                if self.number[self.mid] == self.desired:Â
                    # make flag false                    self.start = FalseÂ
                    # show output in result label                    self.result.setText("Found at index : " + str(self.mid))Â
                    # set color of label to green                    self.label_list[self.mid].setStyleSheet(                                     "border : 2px solid green; "                                     "background-color : lightgreen")Â
                # if not equal to mid value                else:                    # make color grey                    self.label_list[self.mid].setStyleSheet(                                  "border : 1px solid black; "                                  "background-color : grey")Â
                # mid value is higher                if self.number[self.mid] > self.desired:                    # change last index                    self.last = self.mid - 1Â
                # if mid value is smaller                if self.number[self.mid] < self.desired:                    # change first index                    self.first = self.mid + 1Â
    # method called by search button    def search_action(self):Â
        # making flag true        self.start = TrueÂ
        # showing text in result label        self.result.setText("Started searching...")Â
    # method called by pause button    def pause_action(self):Â
        # making flag false        self.start = FalseÂ
        # showing text in result label        self.result.setText("Paused")Â
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# create pyqt5 appApp = QApplication(sys.argv)Â
# create the instance of our Windowwindow = Window()Â
# start the appsys.exit(App.exec()) |
Output :
