Format method
A format method is an API operation that produces a formatted representation by substituting supplied values into a formatting specification.
Tiny Python Projects: Learn coding and testing with puzzles and games
str.format() is a Python string method that produces a new string by replacing formatting fields with supplied values.
- How it is used
- Uses templates to insert variables and control displayed values in phrases, command-line output, and tabular results.
- How deep it goes
- Explains placeholders, positional arguments, precision, field width, and justification, but does not detail advanced formatting internals.
- Examples
- Demonstrates nautical phrases, formatted π values, aligned columns, word-count output, and generated insults.
- What you can do after
- Apply str.format() to build reusable output templates, set numeric precision, and align text or numbers into columns.
100 Java Mistakes and How to Avoid Them
String.format is a Java API method that returns a formatted string constructed from a format string and supplied arguments.
- How it is used
- Formats strings and formatted output by substituting supplied arguments into format specifiers.
- How deep it goes
- Explains argument matching, silent unused arguments, permissive %b and %s behavior, locale effects, and static-analysis limits.
- Examples
- Uses point formatting, day-and-weekend output, greeting methods, and date formatting with reordered arguments.
- What you can do after
- Diagnose mismatched format arguments and apply corrected ordering while interpreting static-analysis warnings selectively.
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Python Workout: 50 ten-minute exercises
str.format is a Python string method that produces formatted text by substituting values into replacement fields.
- How it is used
- Formats mixed values and aligned columns in generated text.
- How deep it goes
- Explains positional fields, tuple unpacking, widths, alignment, padding, and floating-point precision.
- Examples
- Uses a guessed number, Hello world, and sorted people tuples with aligned travel-time columns.
- What you can do after
- Apply it via Python's str.format method to substitute values and produce controlled text layouts.
Read how Python Workout: 50 ten-minute exercises explains format method →
Related concepts
- f-stringalternative to · An f-string is a Python formatted string literal that evaluates embedded expressions and inserts their formatted values into the resulting string.
- format stringuses · A format string is a character sequence containing literal text and directives that specify how supplied values are represented in formatted input or output.
- fmtalternative to · fmt is a software library or package that provides formatted text generation and, in some implementations, formatted input and output operations.
- timestampused by · A timestamp is a value representing a specific point in time, typically associated with an event, observation, or data item.
- __str__part of · __str__ is a Python special method that returns an object's informal, human-readable string representation.
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