Maybe the best reference book for looking up how to do things in PHP - if only you could trust that the author knew what he was talking about.
Sometimes when you are reading a book, the author suddenly makes a simple comment that demonstrates that they have no idea whatever as to what something that they have been discussing actually is. Such is the case in Chapter Three of the book "PHP Cookbook" where the author is discussing the various date and calendar functions available in PHP and how to use them.
One of the "Calendars" that PHP supports with both methods to convert to and from that calendar as well as to manipulate dates in that calendar format is Julian Days. Julian days were first proposed in 1582 but nothing came of it at that time. In 1865 it was proposed again specifically for use by astronomers and was officially adopted by the Royal Astronomical Society in 1884.
The author of the book makes a statement to the effect that using Julian days to reference dates prior to the year 46BCE would annoy purists as he claims that the calendar began in that year. As the 46BCE date has no relevance to Julian Days whatsoever, the author obviously has no idea what Julian Days actually are.
Having spotted one major error in a book where the author demonstrates that they don't know what they are talking about you start to wonder how many similar errors that they might have made in the rest of the book. This might be the best book ever written for showing PHP progerammers how to effectively achieve specific results in all of the different areas covered by the language but for me this one mistake calls into question the rest of the book content and the book is not one that would find a place in my reference library.
This article written by Stephen Chapman, Felgall Pty Ltd.