Extract Numbers from Web Pages with Python: A Quick Regex Guide

Introduction

A user asked about a Python web‑scraping problem; the answer includes a complete example that fetches a page, parses it with lxml.etree, and extracts price data.

url = "http://zw.hainan.gov.cn/wssc/ec/jlyhnkj.html"
resp = requests.get(url)
text = resp.text
parse = etree.HTML(text)
price = parse.xpath("//div[@class='productlist']/ul/li/div[4]/text()")
price = [i.strip() for i in price if i.strip()]
print(price)

The code shows how to clean the extracted list by removing empty strings.

Regex Extraction

To capture numeric values such as "身高180.3cm", a simple regular expression can be used:

\d+\.\d+

For a more flexible solution that matches both integers and decimals, the following pattern is applied to a list of sample strings:

d = ["身高180.3cm", "身高180.3", "身高180.3厘米", "higt180.3cm", "higt180.3厘米", "身高180.3cm", "higt180cm"]
for s in d:
    r = re.findall(r'\d+\.\d+|\d+', s)
    print(r)

This loop prints the numeric part of each string, handling both floating‑point numbers and whole numbers.

Conclusion

The provided examples illustrate how to combine HTTP requests, HTML parsing, and regular expressions in Python to efficiently extract numeric data from web content.