Advanced Search

python db Django 協調フィルタリング GAE

/ Published in: Python
Save to your folder(s)

Expand | Embed | Plain Text

Copy this code and paste it in your HTML 
  1. #models.py
  2. class User(db.Model):
  3.     name=db.StringProperty(required=True)
  4.  
  5. class Product(db.Model):
  6.     product=db.StringProperty(required=True)
  7.  
  8. class UserRate(db.Model):
  9.     ref_user=db.ReferenceProperty(User,collection_name='users')
  10.     ref_product=db.ReferenceProperty(Product,collection_name='products')
  11.     rating=db.IntegerProperty(required=True)
  12.  
  13. #views.py
  14. def makeMap(item1,item2):
  15.     item_list =[item1,item2]
  16.     products = db.GqlQuery("SELECT * FROM Product WHERE product IN :list",list = item_list)
  17.     map_product={}
  18.     for product in products:
  19.         map_user={}
  20. #        print product.product
  21.         key=product.key()
  22. #        print key
  23.         userrates=db.GqlQuery("SELECT * FROM UserRate WHERE ref_product =:1",key)
  24.         for u in userrates:
  25. #            print u.ref_user.name
  26.             map_user[u.ref_user.name]=u.rating
  27. #            print map_user[u.ref_user.name]
  28.         map_product[product.product]=map_user
  29. #        print map_product
  30. #        print '<br><br>'
  31.     return map_product
  32.  
  33. def sim_pearson(item1,item2):
  34.     si={}
  35.     prefs=makeMap(item1,item2)
  36. #    print "prefs="
  37. #    print prefs
  38.     for person in prefs[item1]:
  39.         if person in prefs[item2]: si[person]=1
  40.     n=len(si)
  41. #    print "<br>n="
  42. #    print n  
  43.     if n==0: return 0
  44.     sum1=float(sum([prefs[item1][it] for it in si]))
  45.     sum2=float(sum([prefs[item2][it] for it in si]))
  46. #    print "<br>sum1="
  47. #    print sum1
  48. #    print "<br>sum2="
  49. #    print sum2  
  50.     sum1Sq=float(sum([pow(prefs[item1][it],2) for it in si]))
  51.     sum2Sq=float(sum([pow(prefs[item2][it],2) for it in si]))
  52. #    print "<br>sum1Sq="
  53. #    print sum1Sq
  54. #    print "<br>sum2Sq="
  55. #    print sum2Sq
  56.     pSum=float(sum([prefs[item1][it]*prefs[item2][it] for it in si]))
  57. #    print "<br>pSum ="
  58. #    print pSum
  59.     num=pSum-(sum1*sum2/n)
  60. #    print "<br>num  ="
  61. #    print num
  62.     den=sqrt((sum1Sq-pow(sum1,2)/n)*(sum2Sq-pow(sum2,2)/n))
  63. #    print (sum1Sq-pow(sum1,2)/n)
  64. #    print (sum2Sq-pow(sum2,2)/n)
  65. #    print "<br>den="
  66. #    print den
  67.     if den == 0: return 0
  68.     r=num/den
  69. #    print "<br>r="
  70. #    print r
  71.     return r

Report this snippet


Comments

RSS Icon Subscribe to comments

You need to login to post a comment.