Vincent Gao
f687d261e8
calculateInverse() treated a CDF value of exactly 0.0 as "the guess is the root" and collapsed the bracket with $b = $a, ending the search. inverse() already rejects probability <= 0, so a CDF of 0.0 inside the bisection can only be a float64 underflow at a guess far below the root - never an exact hit. It is just an ordinary "guess too low" and belongs in the existing else branch. The underflow is reached whenever a probe lands many standard deviations from the mean, so the search collapses after two or three iterations and returns whichever midpoint it was holding. BETAINV(0.5, 5000, 5000) gave 0.25, though Beta(a, a) is symmetric and its median is exactly 0.5; BETAINV(0.5, 20000, 3) gave 0.5 against a true 0.99986. Onset is around alpha = 1080 for beta = 1, where the closed form 0.5 ** (1 / alpha) is available to check against. That test also happened to stop the search for shapes where incompleteBeta declines to evaluate at all and returns 0 for every x, so inverse() now rejects alpha + beta above that documented limit up front: the CDF is identically zero there, so no quantile exists to search for. Tests cover a shape x probability grid against scipy reference values plus three checks that need no external oracle: the symmetric median, the Beta(alpha, 1) closed form, and the BETADIST round trip / mirror identity.
PhpSpreadsheet
PhpSpreadsheet is a library written in pure PHP and offers a set of classes that allow you to read and write various spreadsheet file formats such as Excel and LibreOffice Calc.
This is the master branch, and is maintained for security and bug fixes.
PHP Version Support
LTS: For maintained branches, support for PHP versions will only be maintained for a period of six months beyond the end of life of that PHP version. Dropping support for versions after that date will not be considered a breaking change.
Currently the required PHP minimum version is PHP 8.2, and we will support that version until 30th June 2027.
See the composer.json for other requirements.
Installation
See the install instructions.
Documentation
Read more about it, including install instructions, in the official documentation. Or check out the API documentation.
Please ask your support questions on StackOverflow, or have a quick chat on Gitter.
Patreon
I am now running a Patreon to support the work that I do on PhpSpreadsheet.
Supporters will receive access to articles about working with PhpSpreadsheet, and how to use some of its more advanced features.
Posts already available to Patreon supporters:
- The Dating Game
- A look at how MS Excel (and PhpSpreadsheet) handle date and time values.
- Looping the Loop
- Advice on Iterating through the rows and cells in a worksheet.
And for Patrons at levels actively using PhpSpreadsheet:
- Behind the Mask
- A look at Number Format Masks.
The Next Article (currently Work in Progress):
- Formula for Success
- How to debug formulae that don't produce the expected result.
My aim is to post at least one article each month, taking a detailed look at some feature of MS Excel and how to use that feature in PhpSpreadsheet, or on how to perform different activities in PhpSpreadsheet.
Planned posts for the future include topics like:
- Tables
- Structured References
- AutoFiltering
- Array Formulae
- Conditional Formatting
- Data Validation
- Value Binders
- Images
- Charts
After a period of six months exclusive to Patreon supporters, articles will be incorporated into the public documentation for the library.
PHPExcel vs PhpSpreadsheet ?
PhpSpreadsheet is the next version of PHPExcel. It breaks compatibility to dramatically improve the code base quality (namespaces, PSR compliance, use of latest PHP language features, etc.).
Because all efforts have shifted to PhpSpreadsheet, PHPExcel will no longer be maintained. All contributions for PHPExcel, patches and new features, should target PhpSpreadsheet master branch.
Do you need to migrate? There is an automated tool for that.
License
PhpSpreadsheet is licensed under MIT.