A lot of comics

Author: banerjeesamrat

.vscode/settings.json

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+{
+    "python.pythonPath": "/usr/bin/python3.5",
+    "python.linting.enabled": false
+}

Chapter15- KeepingTime, SchedulingTasks,andLaunchingPrograms/alarm.wav

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+import time
+
+def calcProd():
+    # Calculate the product of first 100,000 numbers
+    product=1
+    for i in range(1,100000):
+        product=product*i
+    return product
+
+startTime=time.time()
+prod=calcProd()
+endTime=time.time()
+print("The result is %s digits long."%(len(str(prod))))
+print('Took %s seconds to calculate.' % (endTime - startTime))

Chapter15- KeepingTime, SchedulingTasks,andLaunchingPrograms/calcProd.py

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+#! /usr/bin/python3.5
+
+"""
+
+Author: Samrat Banerjee
+Dated: 08/09/2018
+Description: Project: A simple countdown script.
+
+"""
+
+import time, subprocess,webbrowser
+
+timeLeft=60
+
+while timeLeft>0:
+    print(timeLeft,end=' ')
+    time.sleep(1)
+    timeLeft=timeLeft-1
+
+    # At the end of the countdown, play a sound file.
+    webbrowser.open("https://www.rediff.com/")

Chapter15- KeepingTime, SchedulingTasks,andLaunchingPrograms/countdown.py

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+#! /usr/bin/python3.5
+
+"""
+
+Author: Samrat Banerjee
+Dated: 08/09/2018
+Description: Project: Downloads XKCD comics using multiple threads.
+
+"""
+
+import requests,os,bs4,threading
+
+os.makedirs('xkcd', exist_ok=True) # store comics in ./xkcd
+
+def downloadXkcd(startComic,endComic):
+    for urlNumber in range(startComic, endComic):
+        # Download the page
+        print('Downloading page http://xkcd.com/%s...' %(urlNumber))
+        res = requests.get('http://xkcd.com/%s' % (urlNumber))
+        res.raise_for_status()
+
+        soup=bs4.BeautifulSoup(res.text)
+
+        # Find the url of the comic image
+        comicElem=soup.select('#comic img')
+        if comicElem==[]:
+            print('Could not find comic image.')
+        else:
+            comicURL='https:' + comicElem[0].get('src')
+
+            # Download the image
+            print("Downloading image %s..."%(comicURL))
+            res=requests.get(comicURL)
+            res.raise_for_status()
+
+            # Save the image to ./xkcd
+            imageFile=open(os.path.join('xkcd',os.path.basename(comicURL)),'wb')
+            for chunk in res.iter_content(100000):
+                imageFile.write(chunk)
+            imageFile.close()
+
+
+# Create and start the Thread objects.
+downloadThreads = []             # a list of all the Thread objects
+for i in range(0, 1400, 100):    # loops 14 times, creates 14 threads
+    downloadThread = threading.Thread(target=downloadXkcd, args=(i, i + 99))
+    downloadThreads.append(downloadThread)
+    downloadThread.start()
+
+# Wait for all threads to end.
+for downloadThread in downloadThreads:
+    downloadThread.join()
+print('Done.')

Chapter15- KeepingTime, SchedulingTasks,andLaunchingPrograms/multidownloadXkcd.py

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+#! /usr/bin/python3.5
+
+
+"""
+
+Author: Samrat Banerjee
+Dated: 08/09/2018
+Description: Project: A simple stopwatch program.
+
+"""
+
+import time
+
+# Display the program's instructions.
+print('Press ENTER to begin. Afterwards, press ENTER to "click" the stopwatch. Press Ctrl-C to quit.')
+input()                    # press Enter to begin
+print('Started.')
+startTime = time.time()    # get the first lap's start time
+lastTime = startTime
+lapNum = 1
+
+# Start tracking the lap times.
+try:
+    while True:
+        input()
+        lapTime=round(time.time()-lastTime,2)
+        totalTime=round(time.time()-startTime,2)
+        print('Lap #%s: %s (%s)'%(lapTime,totalTime,lapTime),end=' ')
+        lapNum+=1
+        lastTime=time.time()    # reset the last lap time
+except KeyboardInterrupt:
+    # Handle the Ctrl-C exception to keep its error message from displaying.
+     print('\nDone.') 

Chapter15- KeepingTime, SchedulingTasks,andLaunchingPrograms/stopwatch.py

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+import threading, time
+
+print('Start of program.')
+
+def takeANap():
+    time.sleep(5)
+    print('Wake up!')
+
+threadObj = threading.Thread(target=takeANap)
+threadObj.start()
+
+print('End of program.')