Hi Anatole, I understand your sentiments, and I do understand and respect your viewpoint. However Gordon has been kind enough to quickly make some very clear statements for me regarding where we are at today, and as a result, I'm making progress in solving the problem. I'm afraid that trivializing the matter will impede this process.
If there's any hope in building a grass roots "ground swell" of support for adding fixed decimal support to Flex, it has to come from educating the folks about what we've got, and what the options are. I'm happy others like Jeff want to know more about this. It is time, for those who are unaware of what happens when you expect and require the results and accuracy of decimal math while working with floating point values, to learn and understand what the difference is, the implications, and limitations of being forced to use floating point variables. The problem is far more serious and practical that it is theoretical. To appreciate the complexity of dealing with fixed decimal numbers, take a look at the over 10,000 lines of code in 7 different classes in the Java API which deal directly with fixed decimal support. Make no bones about it, there's a lot more going on than just carefully placed rounding statements. Jeff, the client side as it stands now is incapable of accurately performing any mathematical function with accuracy on arbitrary precision decimal numbers, especially when executed repeatedly. The adding machine on your desk and the same formula within Flash client will never agree with each other 100%. A balance sheet must balance to the penny. A journal entry must balance to the penny. A sales tax rate must be exactly 5.92 percent, etc. Don't depend on the Flash client to do this successfully without adding fixed decimal support of some kind to your application. When doing decimal data entry in the Flash client, if the data is first stored in a Number object before being transferred to the server, the value will appear to change randomly before being stored in the database. It is because some fractions can only be represented in binary as an aproximation (not exact). This is how we encountered the problem. It was a simple CRUD application written to FDS. The object had two fields - Description and Rate. Rate was a Number object in Actionscript, a BigDecimal 7 long with 4 decimal positions on the server. 1.92 was keyed into Rate in Flash, and FDS wrote 1.91 to the database. It's that simple. Anatole, out DAO layer is not able to compensate for this because we're using FDS. FDS passes in a BigDecimal already initialized with the wrong number. The problem, as you rightly point out, is a rounding issue. The problem is precisely that FDS must always be rounding down (because our value of 1.92, converted to double as 1.91999... ends up 1.91 in the database. FDS deserialization is not considering the scale and precision of the destination field during the conversion. If it did, we'd be highly accurate, but not perfectly accurate. After enough iterations, we'd still loose a penny eventually, and the CPA or CFO would storm into my office and say "The system doesn't work right because..." Prior to Flex, I've been working with C++ on the client side with a fixed decimal library which is at least 15 years old, and with IBM midrange business computers developed in the late 70's on the server side, with languages where there is no such thing as a float (ONLY fixed decimals). This is the kind of software/hardware which was developed to handle business transactions over 30 years ago, and much of the world still runs on them. Until Flex and all of the other new technologies have support for fixed decimals and can add up a balance sheet, we will not be able to replace these old back end systems which at the end of the day have to balance the books month in and month out - to the penny. Let's work to educate Flex users about the benefits of fixed decimal math, and ask Adobe to make sure it gets in to the next version. It will help solidify the future of the rich internet application a great deal. Best regards to all, Matt -- Flexcoders Mailing List FAQ: http://groups.yahoo.com/group/flexcoders/files/flexcodersFAQ.txt Search Archives: http://www.mail-archive.com/flexcoders%40yahoogroups.com Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/flexcoders/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
