Create numericalmethod.py

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Author: hemangsk

numericalmethod.py

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+from bs4 import BeautifulSoup
+import urllib2
+import wget
+
+
+print "Welcome to mathforcollege.com Numerical Method Chapters Downloader \n"
+
+
+
+
+#The million dollar base url
+url="http://nm.mathforcollege.com/topics/index.html"
+
+
+#Variables
+filter_stuff=[] #used in function make_things_alright as a temporary array which stores useful links
+chapters=[] #This array will store all the useful links from webpage discarding other links
+pdf_links=[]
+
+def get_page(url):
+    f = urllib2.urlopen(url)
+    page = f.read()
+    f.close()
+    return page
+
+
+def get_next_target(page):
+        start_link = page.find('<a href="')
+        if start_link == -1:
+            return None, 0
+        start_quote = page.find('"', start_link)
+        end_quote = page.find('"', start_quote + 1)
+        url = page[start_quote + 1:end_quote]
+        return url, end_quote
+
+def get_all_links(page):
+        links = []
+        while True:
+            url,endpos = get_next_target(page)
+            if url:
+                links.append(url)
+                page = page[endpos:]
+            else:
+                break
+        return links
+
+def find_pdf_links(y):
+
+        for plink in y:
+            if ('.pdf' in plink and 'http://mathforcollege.com/nm/' in plink and 'ppt' not in plink and 'problem' not in plink and 'quiz' not in plink and 'example' not in plink):
+                #collect_links.append(plink)
+                filename=wget.download(plink)
+
+def make_things_alright(y):
+        #iterators
+        i=0
+        for text in y:
+            if 'http:' not in text and 'https:' not in text and 'mailto' not in text:
+                filter_stuff.append(text)
+                filter_stuff[i]='http://nm.mathforcollege.com/topics/'+text
+                i=i+1
+        return filter_stuff
+
+all_links= get_all_links(get_page(url))
+chapters = make_things_alright(all_links) #filtering links
+
+
+#iterators
+i=0
+
+for text in chapters:
+        i=i+1
+        print "Downloading Chapter "+ i
+        find_pdf_links(get_all_links(get_page(text)))
+
+print "Download Complete!"