使用 PyQt5 的插值搜索可视化工具
在本文中，我们将看到如何制作一个 PyQt5 应用程序，该应用程序将可视化插值搜索算法。
插值搜索是对实例的二进制搜索的改进，其中排序数组中的值是均匀分布的。二分查找总是到中间元素去检查。另一方面，插值搜索可能会根据正在搜索的键的值去不同的位置。例如，如果 key 的值更接近最后一个元素，则插值搜索很可能会向 end 侧开始搜索。
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 a 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 lower higher and position index and flag for searching
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 interpolation search algorithm
6. Check if value lies within the range if not show output as not found else continue
7. If the index of lower index is greater then higher index stop the search and show result as not found
8. Calculate the position index through the interpolation search formula
9. Check if the desired value is at position index if matches show result as found
10. If desired value is not equal then update the lower and higher index according to the desired value.
下面是实现
Python3
# 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 = [10, 12, 13, 16, 18, 19, 20, 21,
22, 23, 24, 33, 35, 42, 47]
# desired value
desired = 24
def __init__(self):
super().__init__()
# setting title
self.setWindowTitle("Interpolation Search ")
# setting geometry
self.setGeometry(100, 100, 600, 400)
# calling method
self.UiComponents()
# showing all the widgets
self.show()
# method for widgets
def UiComponents(self):
# start flag
self.start = False
# list to hold labels
self.label_list = []
# position for keeping index
self.position = 0
# lower index
self.lo = 0
# higher index
self.hi = len(self.number) - 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
label.setAlignment(Qt.AlignTop)
# 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 * 2 + 10)
# adding label to the label list
self.label_list.append(label)
# 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
self.search_button.clicked.connect(self.search_action)
# 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
pause_button.clicked.connect(self.pause_action)
# creating label to show the result
self.result = QLabel("To search : " + str(self.desired), self)
# setting geometry
self.result.setGeometry(350, 280, 200, 40)
# setting style sheet
self.result.setStyleSheet("border : 3px solid black;")
# adding font
self.result.setFont(QFont('Times', 10))
# setting alignment
self.result.setAlignment(Qt.AlignCenter)
# creating a timer object
timer = QTimer(self)
# adding action to timer
timer.timeout.connect(self.showTime)
# update the timer every 200 millisecond
timer.start(200)
# method called by timer
def showTime(self):
# checking if flag is true
if self.start:
# Interpolation Search
# checking if desired number is with in the range
if (self.desired < self.number[self.lo] or
self.desired > self.number[self.hi]):
# make flag false
self.start = False
# show result as not found
self.result.setText("Not Found")
# if lower index become greater then higher index
if self.lo > self.hi:
# make flag false
self.start = False
# show result as not found
self.result.setText("Not Found")
else:
# lower index is equal to higher index
if self.lo == self.hi:
# checking if it matches desired value
if self.number[self.lo] == self.desired:
# show result
self.result.setText("Found at index : " + str(self.lo))
# make result label color green
self.label_list[self.lo].setStyleSheet(
"border : 2px solid green;"
"background-color : lightgreen;")
else:
# make result color grey
self.label_list[self.lo].setStyleSheet(
"border : 1px solid black;"
"background-color : grey;")
# Probing the position with keeping
# uniform distribution in mind.
self.position = self.lo + int(((float(self.hi - self.lo) /
( self.number[self.hi] - self.number[self.lo])) *
(self.desired - self.number[self.lo])))
# checking if the position matches with desired value position
if self.number[self.position] == self.desired:
# make flag false
self.start = False
# show result and make label color green
self.result.setText("Found at position : " + str(self.position))
self.label_list[self.position].setStyleSheet(
"border : 2px solid green;"
"background-color : lightgreen;")
else:
# make label color grey
self.label_list[self.position].setStyleSheet(
"border : 1px solid black;"
"background-color : grey;")
# If desired is larger, desired is in upper part
if self.number[self.position] < self.desired:
# updating lowe index
self.lo = self.position + 1
# If desired is smaller, desired is in lower part
else:
# updating higher index
self.hi = self.position - 1
# 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
self.result.setText("Paused")
# create pyqt5 app
App = QApplication(sys.argv)
# create the instance of our Window
window = Window()
# start the app
sys.exit(App.exec())输出 ：