Chapter 12 - Summary¶
Chapter 12 included the following concepts from computing.
- Block of Code - A block of code in Python is one or more code statements that are part of a loop, conditional, function, or procedure.
- Boolean Expression - A Boolean expression is one that is either true or false. This is also called a logical expression.
- Complex Conditionals - A complex conditional has two or more logical
expressions joined by the keywords
and
,or
, ornot
. - Condition - A condition is something that is either true or false. This is also called a Boolean expression or a logical expression.
- Conditional Execution - Conditional execution means that one or more statements are executed only when a condition (logical expression) is true. This is also called a conditional. The statements that are executed when the condition is true are called the body of the loop.
- Decision - A decision is a choice between at least two choices.
- Flowchart - A flowchart is a diagram that shows the execution paths for a program. The conditionals are shown as diamonds.
- Logical Expression - A logical expression is one that is either true or
false, like
x == 3
which will return true if x is equal to 3. This is also called a Boolean expression. - Negation - When you negate a logical expression if the original expression is true the negated expression is false and if the original expression is false the negated expression is true.
Summary of Python Keywords and Functions¶
- And - The keyword
and
is used to join two logical expressions and then both of the logical expressions must be true for the joined expression to be true. - Else - The keyword
else
is used to execute one or more statements in a block following theelse
when the condition in theif
part of the statement is false. Anelse
must always have anif
statement before it. - If - The Python keyword
if
is used to start a condition. It is followed by a Boolean expression and then has one or more statements in the body of the loop that are executed only if the Boolean expression is true. - Not - The keyword
not
is used to negate a logical expression. If the original expression is true the negated expression is false and if the original expression is false the negated expression is true.