Contents
xvi
Mistakes Will Happen 26
Some Unusual Cases 27
Summary 28
Exercises 29
Chapter 3: Variables — Names for Values 31
Referring to Data — Using Names for Data 31
Changing Data Through Names 33
Copying Data 33
Names You Can’t Use and Some Rules 34
Using More Built-in Types 34
Tuples — Unchanging Sequences of Data 34
Lists — Changeable Sequences of Data 37
Dictionaries — Groupings of Data Indexed by Name 39
Treating a String Like a List 41
Special Types 42
Other Common Sequence Properties 43
Referencing the Last Elements 43
Ranges of Sequences 44
Growing Lists by Appending Sequences 45
Using Lists to Temporarily Store Data 45
Working with Sets 46
Summary 47
Exercises 48
Part II: Python Language and the Standard Library 49
Chapter 4: Making Decisions 51
Comparing Values — Are They the Same? 51
Doing the Opposite — Not Equal 53
Comparing Values — Which One Is More? 54
More Than or Equal, Less Than or Equal 55
Reversing True and False 56
Looking for the Results of More Than One Comparison 56
How to Get Decisions Made 57
Repetition 60
How to Do Something — Again and Again 60
Stopping the Repetition 62
Handling Errors 65
Trying Things Out 65
