TeXipedia

lbrack

Produces a left square bracket character, commonly used for mathematical notation and array delimiters.

Overview

Essential for mathematical writing and computer science notation, serving multiple purposes in formal expressions and programming contexts.

  • Frequently used in set notation and matrix representations
  • Pairs with \rbrack to create matching bracket pairs
  • Common in programming language syntax examples and algorithm descriptions
  • Particularly useful when standard keyboard brackets might conflict with other LaTeX commands

Examples

Using left bracket in a set builder notation.

A=[x∈R:x>0]A = \lbrack x \in \mathbb{R} : x > 0 \rbrack 
A = \lbrack x \in \mathbb{R} : x > 0 \rbrack

Matrix representation with explicit brackets.

M=[aij]n×nM = \lbrack a_{ij} \rbrack_{n \times n} 
M = \lbrack a_{ij} \rbrack_{n \times n}

Interval notation with left bracket for closed endpoint.

x∈[0,∞)x \in \lbrack 0, \infty) 
x \in \lbrack 0, \infty)