forked from https://github.com/symfony/symfony
This PR was squashed before being merged into the 2.7 branch (closes #21769).
Discussion
----------
[Form] Improve rounding precision
| Q | A
| ------------- | ---
| Branch? | 2.7
| Bug fix? | yes
| New feature? | no
| BC breaks? | no
| Deprecations? | no
| Tests pass? | yes
| Fixed tickets | 21734
| License | MIT
| Doc PR |
For full details see https://github.com/symfony/symfony/issues/21734 from https://github.com/symfony/symfony/issues/21734#issuecomment-282552802 onwards.
Excerpt:
```php
$number = floor(37.37*100); // double(3736)
var_dump($number);
$number = floor(bcmul(37.37, 100)); // double(3737)
var_dump($number);
```
From http://php.net/manual/en/language.types.float.php#language.types.float:
> Additionally, rational numbers that are exactly representable as floating point numbers in base 10, like 0.1 or 0.7, do not have an exact representation as floating point numbers in base 2, which is used internally, no matter the size of the mantissa. Hence, they cannot be converted into their internal binary counterparts without a small loss of precision. This can lead to confusing results: for example, floor((0.1+0.7)*10) will usually return 7 instead of the expected 8, since the internal representation will be something like 7.9999999999999991118....
>
> So never trust floating number results to the last digit, and do not compare floating point numbers directly for equality. If higher precision is necessary, the arbitrary precision math functions and gmp functions are available.
Commits
-------
|
||
---|---|---|
.composer | ||
.github | ||
src/Symfony | ||
.editorconfig | ||
.gitignore | ||
.php_cs.dist | ||
.travis.yml | ||
appveyor.yml | ||
CHANGELOG-2.2.md | ||
CHANGELOG-2.3.md | ||
CHANGELOG-2.4.md | ||
CHANGELOG-2.5.md | ||
CHANGELOG-2.6.md | ||
CHANGELOG-2.7.md | ||
composer.json | ||
CONTRIBUTING.md | ||
CONTRIBUTORS.md | ||
LICENSE | ||
phpunit | ||
phpunit.xml.dist | ||
README.md | ||
UPGRADE-2.1.md | ||
UPGRADE-2.2.md | ||
UPGRADE-2.3.md | ||
UPGRADE-2.4.md | ||
UPGRADE-2.5.md | ||
UPGRADE-2.6.md | ||
UPGRADE-2.7.md | ||
UPGRADE-3.0.md |
Symfony is a PHP framework for web applications and a set of reusable PHP components. Symfony is used by thousands of web applications (including BlaBlaCar.com and Spotify.com) and most of the popular PHP projects (including Drupal and Magento).
Installation
- Install Symfony with Composer or with our own installer (see requirements details).
- Symfony follows the semantic versioning strictly, publishes "Long Term Support" (LTS) versions and has a release process that is predictable and business-friendly.
Documentation
- Read the Getting Started guide if you are new to Symfony.
- Try the Symfony Demo application to learn Symfony in practice.
- Master Symfony with the Guides and Tutorials, the Components docs and the Best Practices reference.
Community
- Join the Symfony Community and meet other members at the Symfony events.
- Get Symfony support on StackOverflow, Slack, IRC, etc.
- Follow us on GitHub, Twitter and Facebook.
Contributing
Symfony is an Open Source, community-driven project with thousands of contributors. Join them contributing code or contributing documentation.
Security Issues
If you discover a security vulnerability within Symfony, please follow our disclosure procedure.
About Us
Symfony development is sponsored by SensioLabs, lead by the Symfony Core Team and supported by Symfony contributors.