Python Data Hierarchy

An introduction to main Python data hierarchy

Note: This will be updated and linked to further content development

A subset of the data types that are built into Python.

Numbers

We use numbers all the time. Numbers can either be integrals or non-integrals.

Arithmetic operators and arithmetic built-in functions will return numbers. Numeric objects are immutable. In other words, when a number is created, it cannot be changes or a number within it be replaced. Python numbers are the same as mathematical numbers, but subject to the limitations of numerical representation in computers.

• Integral

  • Integers: A whole number that can be positive, negative or zero.

  • Booleans: A data type that has one of two possible values (true or false)

• Non-integral

  • Floats: A number that has a decimal place. We use float data type when we need more precision.

  • Decimals: The decimal data type is an exact numeric defined by its precision (total number of digits) and scale (number of digits to the right of the decimal point).

  • Complex numbers: A combination of a real and an imaginary number in the form a + bi where a and b are real numbers, and i is the "unit imaginary number" √(−1)

  • Fractions: Fraction of a number, for example 1/8, 3/4, 5/8 etc.

Collections

• Sequences: Sequences represent finite ordered sets indexed by natural numbers.

  • Mutable: Mutable sequences can be changed after they are created.

    • Lists

  • Immutable: Immutable sequences can NOT be changed after they are created.

    • Tuples

    • Strings

• Sets

  • Mutable

    • Sets

  • Immutable

    • Frozen sets

• Mappings: These represent finite sets of objects indexed by arbitrary index sets.

  • Dictionaries: These represent finite sets of objects indexed by nearly arbitrary values.

• Callables

  • User-Defined Functions

  • Generators

  • Classes

  • Instance Methods

  • Built-in Functions (for example; len(), open())

  • Built-in Methods (for example; my_list.append(x))

Singletons

• None

  • It means that there is no value (empty record). This can be used in function to explicitly return nothing. This type has a single value (singletons). This object is accessed through the built-in name None. None truth value is false.

• Ellipsis

  • Similar to None, Ellipsis has a single value. This object is accessed through the built-in name Ellipsis. It is used to indicate the presence of the "..." syntax in a slice. Ellipsis

    truth value is true.

You can read more on Python Data Types in Python documentation here