Add files via upload

2018-02-20 11:34:52 +01:00
parent 500c278d39
commit a642073d3a
6 changed files with 520 additions and 8 deletions
@@ -0,0 +1,133 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+
+"""
+ZetCode Tkinter e-book
+
+This script produces a long-running task of calculating 
+a large Pi number, while keeping the GUI responsive.
+
+Author: Jan Bodnar
+Last modified: January 2016
+Website: www.zetcode.com
+"""
+
+from tkinter import (Tk, BOTH, Text, E, W, S, N, END, 
+    NORMAL, DISABLED, StringVar)
+from tkinter.ttk import Frame, Label, Button, Progressbar, Entry
+from tkinter import scrolledtext
+
+from multiprocessing import Queue, Process
+import queue 
+from decimal import Decimal, getcontext
+
+DELAY1 = 80
+DELAY2 = 20
+
+class Example(Frame):
+  
+    def __init__(self, parent, q):
+        Frame.__init__(self, parent)   
+         
+        self.queue = q 
+        self.parent = parent
+        self.initUI()
+        
+        
+    def initUI(self):
+      
+        self.parent.title("Pi computation")
+        self.pack(fill=BOTH, expand=True)
+        
+        self.grid_columnconfigure(4, weight=1)
+        self.grid_rowconfigure(3, weight=1)
+        
+        lbl1 = Label(self, text="Digits:")
+        lbl1.grid(row=0, column=0, sticky=E, padx=10, pady=10)
+        
+        self.ent1 = Entry(self, width=10)
+        self.ent1.insert(END, "4000")
+        self.ent1.grid(row=0, column=1, sticky=W)
+        
+        lbl2 = Label(self, text="Accuracy:")
+        lbl2.grid(row=0, column=2, sticky=E, padx=10, pady=10)
+
+        self.ent2 = Entry(self, width=10)
+        self.ent2.insert(END, "100")
+        self.ent2.grid(row=0, column=3, sticky=W)        
+        
+        self.startBtn = Button(self, text="Start", 
+            command=self.onStart)
+        self.startBtn.grid(row=1, column=0, padx=10, pady=5, sticky=W)
+        
+        self.pbar = Progressbar(self, mode='indeterminate')        
+        self.pbar.grid(row=1, column=1, columnspan=3, sticky=W+E)     
+        
+        self.txt = scrolledtext.ScrolledText(self)  
+        self.txt.grid(row=2, column=0, rowspan=4, padx=10, pady=5,
+            columnspan=5, sticky=E+W+S+N)
+       
+        
+    def onStart(self):
+        
+        self.startBtn.config(state=DISABLED)
+        self.txt.delete("1.0", END)
+        
+        self.digits = int(self.ent1.get())
+        self.accuracy = int(self.ent2.get())
+        
+        self.p1 = Process(target=self.generatePi, args=(self.queue,))
+        self.p1.start()
+        self.pbar.start(DELAY2)
+        self.after(DELAY1, self.onGetValue)
+        
+       
+    def onGetValue(self):
+        
+        if (self.p1.is_alive()):
+            
+            self.after(DELAY1, self.onGetValue)
+            return
+        else:    
+        
+            try:
+                self.txt.insert('end', self.queue.get(0))
+                self.txt.insert('end', "\n")
+                self.pbar.stop()
+                self.startBtn.config(state=NORMAL)
+            
+            except queue.Empty:
+                print("queue is empty")
+            
+            
+    def generatePi(self, queue):
+        
+        getcontext().prec = self.digits
+        
+        pi = Decimal(0)
+        k = 0
+        n = self.accuracy
+        
+        while k < n:
+            pi += (Decimal(1)/(16**k))*((Decimal(4)/(8*k+1)) - \
+                (Decimal(2)/(8*k+4)) - (Decimal(1)/(8*k+5))- \
+                (Decimal(1)/(8*k+6)))
+            k += 1
+            print (self.p1.is_alive())
+            
+        queue.put(pi)    
+        print("end")    
+
+
+def main():
+    
+    q = Queue()
+  
+    root = Tk()
+    root.geometry("400x350+300+300")
+    app = Example(root, q)
+    root.mainloop()  
+
+
+if __name__ == '__main__':
+    main()