String formatting (sprintf) in MATLAB

Introduction

String formatting helps you create text with numbers or words arranged neatly. It makes your output clear and easy to read.

When you want to show numbers with a fixed number of decimal places.

When you need to combine text and numbers in one message.

When you want to create a formatted report or label.

When you want to prepare data for saving or printing in a specific style.

Syntax

MATLAB

str = sprintf(formatSpec, A, ...)

formatSpec is a string that tells how to format the data, like '%d' for integers or '%0.2f' for floats with 2 decimals.

A, ... are the values you want to insert into the format string.

Examples

Inserts the word 'world' into the text.

MATLAB

str = sprintf('Hello %s!', 'world')

Formats the number 42 as an integer.

MATLAB

str = sprintf('Value: %d', 42)

Shows the number with 2 decimal places.

MATLAB

str = sprintf('Pi approx: %.2f', 3.14159)

Formats two numbers with 1 decimal place each.

MATLAB

str = sprintf('Coordinates: (%.1f, %.1f)', 3.5, 7.2)

Sample Program

This program creates a formatted string with a name, age, and height, then shows it.

MATLAB

name = 'Alice';
age = 30;
height = 1.68;

info = sprintf('Name: %s\nAge: %d years\nHeight: %.2f meters', name, age, height);

disp(info)

Important Notes

Use %% in the format string to print a percent sign.

If you give fewer values than format specifiers, MATLAB will give an error.

You can format strings, integers, floats, and more using different codes like %s, %d, %f.

Summary

sprintf creates formatted text by inserting values into a template string.

Use format specifiers like %s for strings, %d for integers, and %f for floating-point numbers.

It helps make output clear and nicely arranged.