Community Learn Tools Library Leisure
search
English
Home > Backend Development > PHP Tutorial > php round函数bug

php round函数bug

WBOY
Release： 2016-06-06 20:14:55
Original
1324 people have browsed it

算增长率的时候，用round来截取小数点后两位
但是后来去数据库看数据的时候，大部分数据都可以，但是有一部分出现错误

调试后发现
-8.04554643785644
round后变成
-8.04000000000001

这个bug出现几率还挺高
在另一个脚本中测试，同样的数据正常截取

回复内容：

算增长率的时候，用round来截取小数点后两位
但是后来去数据库看数据的时候，大部分数据都可以，但是有一部分出现错误

调试后发现
-8.04554643785644
round后变成
-8.04000000000001

这个bug出现几率还挺高
在另一个脚本中测试，同样的数据正常截取

不算bug吧，凡是涉及到浮点数问题肯定有精度误差的，用的时候注意一下就行了

Related labels：
php
source：php.cn
Previous article：php微信用户信息接口 Next article：thinkphp 微信token验证失败
Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
Latest Articles by Author
Latest Issues
PHP arrays obtained from URL parameters do not behave as expected I have a URL parameter that contains the category ID and I want to treat it as an array li...
From 2024-04-06 22:09:02
0
1
1428
Where should I place CustomLog directive in apache I'm using php:7.2-apachedocker. I need to disable health check url login access log. Based...
From 2024-04-06 22:03:59
0
1
990
What is the format of the variables in the return value? I am a new learner of php. I found a piece of code: if($x<time()){return[false,'error']...
From 2024-04-06 21:55:20
0
1
778
Problems encountered when using opentbs to generate odt files: values ​​of the same key are displayed in the same row instead of separate columns. I'm using a library called OpenTbs to create odt using PHP, I'm using it because columns a...
From 2024-04-06 20:18:18
0
1
483
Group MySQL results by ID for looping over I have a table with flight data in mysql. I'm writing a php code that will group and displ...
From 2024-04-06 17:27:56
0
1
406
Related Topics
More>
Popular Recommendations
Popular Tutorials
More>
Related Tutorials
Popular Recommendations
Latest courses
Latest Downloads
More>
Web Effects
Website Source Code
Website Materials
Front End Template