public void CountSimilarity(BookRecommenderContext db)
{
List <BookSimilarityInformation> books = new List <BookSimilarityInformation>();
foreach (int bookIDI in bookIDs)
{
Book bookI = db.Books.Find(bookIDI);
List <Author> authorsI = bookI.GetAuthors(db).ToList();
List <Genre> genresI = bookI.GetGenres(db).ToList();
BookSimilarityInformation bookInfoI =
new BookSimilarityInformation(bookI.BookId, authorsI, genresI);
books.Add(bookInfoI);
}
for (int bookIndex1 = 0; bookIndex1 < books.Count; bookIndex1++)
{
for (int bookIndex2 = 0; bookIndex2 < books.Count; bookIndex2++)
{
if (bookIndex1 + bookIndex2 >= books.Count)
{
continue;
}
BookSimilarityInformation bookInfo1 = books[bookIndex1];
BookSimilarityInformation bookInfo2 = books[bookIndex2];
double simValue = Similarity(bookInfo1, bookInfo2);
this.matrix[bookIndex1, bookIndex2] = simValue;
this.matrix[bookIndex2, bookIndex1] = simValue;
}
}
}
private double Similarity(BookSimilarityInformation bookInfo1,
BookSimilarityInformation bookInfo2)
{
List <Author> authors1 = bookInfo1.authors;
List <Genre> genres1 = bookInfo1.genres;
List <Author> authors2 = bookInfo2.authors;
List <Genre> genres2 = bookInfo2.genres;
double similarity = 0;
similarity += JaccardSimilarity(authors1, authors2);
similarity += JaccardSimilarity(genres1, genres2);
return(similarity);
}
