• Save
Linked lists
Upcoming SlideShare
Loading in...5

Like this? Share it with your network

  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Be the first to comment
    Be the first to like this
No Downloads


Total Views
On Slideshare
From Embeds
Number of Embeds



Embeds 2 2

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

    No notes for slide


  • 1. Linked Lists
  • 2. (Intentionally left blank)
  • 3. What are linked lists?Linked lists are data structures where nodes point to the next nodes or end of the list. http://en.wikipedia.org/wiki/Linked_list
  • 4. What are types of linked listsSingly: linked lists contain nodes which have a data field as well as a next field, which points tothe next node in the linked listDoubly: is a linked list where each node contains, besides the next-node link, a second linkfield pointing to the previous node in the sequence. The two links may be called forward(s)and backwards, or next and prev(ious).Multiply: is a linked list where each node contains two or more link fields, each field beingused to connect the same set of data records in a different order.
  • 5. How are linked lists used? They can be used to implement several other common abstract data types, including stacks, queues, associative arrays, databases, file systems, and symbolic expressions.Example: MongoDB storage enginehttp://blog.fiesta.cc/post/13975691790/mongosv-live-blog-mongodbs-storage-engine-bit-by-bit
  • 6. Linked List use example: Stack C++ typedef struct stackNode { int data; struct stackNode *nxtptr; } StackNode_t; http://stackoverflow.com/questions/5552394/typedef-and-linked-list
  • 7. Why am I talking about Linked Lists? http://funfax.tumblr.com/
  • 8. Earlier this week Hard released the MARC21 library metadata. http://openmetadata.lib.harvard.edu/
  • 9. This is a big deal. Bibliographic MARC data licensing is very expensive.Marcive charges on the low end at $1,400/year for academic titles. Amazon like datasets can reach 5 figures por year. http://home.marcive.com/index.php?option=com_content&view=article&id=52&Itemid=31
  • 10. What is MARC21? MAchine Readable Catalog (MARC) is a metadatatransmission standard based on ANSI Z39.2 (now ISO 2709) standard . http://en.wikipedia.org/wiki/MARC_standards http://www.loc.gov/marc/
  • 11. This is the MARC21 field list:http://www.loc.gov/marc/bibliographic/ecbdlist.html This is one record: http://caffed.net/record.txt http://hipsterorjesus.com/
  • 12. The Harvard dataset is 10GB in MARC21 format separated into 14 files. Linked Lists are not random access data formats. To utilize the data it must be converted to something else. A document store based system would be the most optimal.
  • 13. My goal is to pull the data save it to a Mongo database And make it searchable via a web front end.My current progress - creating a parsing script thattraverses the files and saves it to the Mongo database.Next steps:- Create REST interface to MongoDB server- Create simple front end that searche using REST interface- Release source on Github- …- Profit!!!
  • 14. MongoDB http://www.mongodb.org/ MARC parsing libraries: Rubyhttps://github.com/ruby-marc/ruby-marc PHPhttp://pear.php.net/package/File_MARC/ Python https://github.com/edsu/pymarc