left-continuous real function
左连续函数
Meaning in context
A real function is left-continuous at a if its limit along domain points increasing to a equals f(a).
实函数在 a 处的左极限等于 f(a),则称其在该点左连续。
Example
is left-continuous at .
Usage and distinctions
At an interval endpoint only the side belonging to the domain is tested.
Recommended reading in this subject · Preparation & skip guidance
Definition sources
- Michael Taylor — Introduction to Analysis in One Variable§3.1, relative-domain continuity · Checked 2026-10-14
- OpenStax — Calculus Volume 1§2.4, Continuity from the Right and from the Left, left-continuity definition · Checked 2026-10-15
Translation sources
- 中国矿业大学数学学院 — 数学分析讲义,第四章§1 一、函数在一点的连续性, 定义2 · Checked 2026-10-14