AmigaOS Manual: Python Elements of Python

Data types

Arrays

Python has four types of arrays (data collections) with different properties:

• Lists: duplicate members are allowed, lists are ordered and indexed, and their content can be changed.
• Tuples: duplicate members are allowed, tuples are ordered and indexed, and their content cannot be changed.
• Sets: duplicate members are not allowed, sets are unordered and unindexed, and their content cannot be changed.
• Dictionaries: duplicate members are not allowed, dictionaries are unordered but indexed, and their content can be changed.

Lists

Python has the following functions for the lists

Function	Explanation
cmp ( <firstList>, <secondList> )	Compare lists <firstList> and <secondList>.
len ( <list> )	Get the number of elements on the list <list>. See len() for more information.
max ( <list> )	Get the maximum valued element on the list <list>. See max() for more information.
min ( <list> )	Get the minimum valued element on the list <list>. See min() for more information.
list ( <tuple> )	Convert the tuple <tuple> into a list. See list() for more information.

and the following methods for the list objects

Method	Explanation
<list>.append ( <object> )	Append an object <object> to the list <list>.
<list>.count ( <object> )	Count how many times object <object> appears on the list <list>.
<list>.extend ( <secondList> )	Append list <secondList> into the list <list>.
<list>.index ( <object> )	Find the first appearance of the object <object> on the list.
<list>.insert ( <index>, <object> )	Insert object <object> into the list <list> at offset <index>.
<list>.pop ( [<index>] )	Remove and return the last object from the list <list> or an object at the supplied offset.
<list>.remove ( <object> )	Remove object <object> from the list <list>.
<list>.reverse ()	Reverses the list <list> order.
<list>.sort ( [<function>] )	Sort the list <list>. Uses the optional compare function <function>, if given.

Operators

Arithmetic operators

Operator	Name	Explanation
+	Plus	Adds the two objects.
-	Minus	Either gives a negative number or gives the subtraction of one number from the other.
*	Multiply	Gives the multiplication of the two numbers or returns the string repeated that many times.
**	Power	Returns x to the power of y.
/	Divide	Divide x by y.
//	Floor Division	Returns the floor of the quotient.
%	Modulo	Returns the remainder of the division.

Comparison operators

Operator	Name	Explanation
<	Less Than	Returns whether x is less than y. All comparison operators return 1 for true and 0 for false. This is equivalent to the special variables True and False respectively. Note the capitalization of these variables' names.
>	Greater Than	Returns whether x is greater than y.
<=	Less Than or Equal To	Returns whether x is less than or equal to y.
>=	Greater Than or Equal To	Returns whether x is greater than or equal to y.
==	Equal To	Compares if the objects are equal.
!=	Not Equal To	Compares if the objects are not equal.

Assignment Operators

Operator	Name	Explanation
=	Assignment	Assigns values from right side operands to left side operand.
+=	Addition and assignment	Adds right operand to the left operand and assigns the result to left operand.
-=	Subtraction and assignment	Subtracts right operand from the left operand and assigns the result to left operand.
*=	Multiplication and assignment	Multiplies right operand with the left operand and assigns the result to left operand.
/=	Division and assignment	Divides left operand with the right operand and assigns the result to left operand.
%=	Modulo and assignment	Takes modulus using two operands and assigns the result to left operand.
**=	Power of and assignment	Performs exponential (power) calculation on operators and assigns value to the left operand.
//=	Floor division and assignment	Performs floor division on operators and assigns value to the left operand.

Logical Operators

Operator	Name	Explanation
not	Boolean NOT	If x is True, it returns False. If x is False, it returns True.
and	Boolean AND	x and y returns False if x is False, else it returns evaluation of y.
or	Boolean OR	If x is True, it returns True, else it returns evaluation of y.

Bitwise Operations on Integer Types

Operator	Name	Explanation
<<	Left Shift	Shifts the bits of the number to the left by the number of bits specified.
>>	Right Shift	Shifts the bits of the number to the right by the number of bits specified.
&	Bitwise AND	Bitwise AND of the numbers.
|	Bitwise OR	Bitwise OR of the numbers.
^	Bitwise XOR	Bitwise XOR of the numbers.
~	Bitwise Invert	The bitwise inversion of x.