Programming Bootcamp for Scientists #21

00:00 Dictionaries

00:40 Windows: mapping file extensions (.py) to an action in Windows File Explorer; The "where" command of Windows.

05:15 What is a Dictionary? ( Hash, Mapcar)

06:40 When to use Dictionaries?

07:31 Create dictionary

10:05 Dictionary keys

10:48 Loop over keys()

11:26 Loop using items()

12:25 Dictionary values()

12:50 Not existing key

13:15 Get key - get()

16:20 Does the key exist? (in)

17:05 How can you search among the values? Does the value exist? - values()

19:00 How dictionaries work? What is hashing?

23:25 Delete key (del, pop)

25:25 List of dictionaries

29:35 In the lambda/map case we did not use key= while in the sort-case we did. Why?

31:35 Shared dictionary - skipped

31:55 tuples as dictionary keys

32:35 numbers as dictionary keys

32:45 Sort dictionary by value

38:00 So at the end, are the keys kept in order in the dictionary or not?

40:42 A few more words about hashing. Hashing algorithms: (md5, sha1). Comparing files.

42:55 Dictionaries vs. lists.

43:40 Exercise: count characters

44:20 Exercise: count words

44:50 Exercise: count words from a file

45:10 Apache log

47:13 Exercise: combine lists again

47:33 Exercise: counting DNA bases

48:03 Exercise: count Amino Acids

48:19 Exercise: List of dictionaries

50:00 Exercise: Dictionary of dictionaries

50:40 Exercise: Age limit with dictionaries