A programming language involves two closely interleaved topics. On
one hand, there are the
statement
constructs that
process information inside the computer, with visible effects on the
various external devices. On the other hand are the various types of
data and relationship structures for organizing the information
manipluated by the program.
This part describes the most commonly-used Python statements,
sticking with basic numeric data types. Part II, “Data Structures” will
present a reasonably complete set of built-in data types and features
for Python. While the two are tightly interwoven, we pick the statements
as more fundamental because we we can (and will) add new data types.
Indeed, the essential thrust of object-oriented programming (covered in
Part III, “Data + Processing = Objects”) is the creation of new data types.
Some of the examples in this part refer to the rules of various
common casino games. Knowledge of casino gambling is not essential to
understanding the language or this part of the book. We don't endorse
casino gambling. Indeed, many of the exercises reveal the magnitude of
the house edge in most casino games. However, casino games have just the
right level of algorithmic complexity to make for excellent programming
exercises.
In Chapter 3, Getting Started
we'll describe the basics of
computer programming, installing a Python interpreter, using Python
interactively, and writing simple scripts. In Chapter 4, Simple Numeric Expressions and Output
we'll introduce the
print
statement, and arithmetic expressions including the numeric data types,
operators, conversions, and some built-in functions. We'll expand on
this in Chapter 5, Advanced Expressions
. We'll introduce variables, the
assignment statement, and input in Chapter 6, Variables, Assignment and Input
, allowing
us to create simple input-process-output programs. When we add truth,
comparisons, conditional processing, iterative processing and assertions
in Chapter 7, Truth, Comparison and Conditional
Processing
, we'll have all the tools necessary for
programming. In Chapter 9, Functions
and Chapter 10, Additional Notes On Functions
, we'll show how to define and use functions, the
first of many tools for organizing programs to make them
understandable.
