Talk:BackwardCompatibility
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+ | many things in the phpipliines are cheaper than the USA prices but all electronics and electrical items like fans etc cost SO much more in most cases you could buy it in the usa and ship it there more cheaply. laptops fall into the latter category. even a cheap one with no memory and tiny hard drive you or i wouldn't even consider buying in the usa will cost you 2 to 3 times the US price for a good one. prices to ship things there can make the difference, and the customs list is often viewed as a shopping list by some unscrupulous postal corp employees en route, but if you're traveling there, definitely bring one along to save money. i priced one last year at $800 that i could buy here for $250. even a $14 20 fan from walmart costs over $60 there, but a fan from here wont work because you needs a 220v one. but most adapters for computers will now run off 220v as well as 110v so that's not a problem with them. there'll most likely be no power issue just read on the adapter and make sure it can also run on 220v. unlike Europe they use 60 cycles in the phpipliines like they USA you may also have to buy a smart buddy plug in wifi module that plugs into a usb port and have a sim card cell phone also far cheaper here to buy smart buddy loads for and transfer the time to the computer, as wifi isn't free in many places there, usually requiring you to pass a load to your computer to get on line. the good side to that IS the loads time you buy on a little smart buddy card are very cheap 300p roughly $6 And are available in most corner sari sari stores. and calling time there for smart COMMUNICATIONS is much cheaper than in the USA, but stay well clear of Globelines. they have weak unreliable signal and charge massive amounts and apparently can imprison philippine citizens for non payment of their exorbitant bills | ||
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+ | --Open 13:37, 23 October 2013 (CEST) | ||
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Revision as of 11:37, 23 October 2013
Regarding BackwardCompatibility and, in particular, Functional Compatibility, you suggest that the output must be "the same result", which implies that only deterministic functions can achieve functional compatibility.
-- dmbarbour?
This is a little bit too mathematical point of view. I was only using common sense. In particular, if the behaviour was non-deterministic in previous version, then the behaviour shall be still non-deterministic. That is the same result I had in mind. Mathematician would say that the probability distribution remains unchanged. OK?
--JaroslavTulach 05:52, 28 August 2009 (UTC)
It seems to me that Functional Compatibility would be met with much looser restrictions: that the output must not further restrict any pre-conditions, and must continue to meet all post-conditions, specified for the function. I.e the "same" result isn't required, but a result that remains within functional specifications is required. This is especially useful when describing updates to, say, constraint programming paradigms and situations where non-determinism is involved or allowed.
-- dmbarbour?
First of all same result means, same output with the same arguments. API can definitely evolve to accept more inputs. Doing that correctly is in fact the art of Evolving the API Universe correctly.
Your comment seems to exhibit the common contention between rationalism and empiricism. It would be right, correct and beautiful if the compatibility was specified by contra-variance in preconditions and co-variance in post-conditions. The problem in real world however is that pre or post conditions are usually unspecified. I come from a project where I have to convince hundred programmers to keep BackwardCompatibility. In such environment one has to be over-demanding. I have to ask for more to get at least a bit of compatibility. Thus I define the functional compatibility so strictly. I use the Amoeba Model to claim that the actual behaviour is more important than the intended one. I say that the way things work (even if buggy) is more important than any specification. This is reasonable approach from one point: It puts all the blame on the author of the API. This is not really fair, but it seems to be the only practical way to get at least a bit of BackwardCompatibility.
--JaroslavTulach 05:52, 28 August 2009 (UTC)
Achieving the same result should be another level above functional compatibility. Or perhaps the above could be a lower level, like 'interface' compatibility. But coupling at the level of 'functional compatibility' would then be a clearer no-no: it means the project is coupled to the implementation rather than the interface.
-- dmbarbour?
I also suggest to Code Against Interfaces, Not Implementations, however the truth is that the implementation always leaks. Users of the API do not start by reading a specification. They are quite clueless. They prototype and if it works, they are done. What happens in next version is behind their horizon. So I think that in practise almost every project gets tight to particular implementation of an API.
As I rationalistic person I would find it very good if your approach could be merged with the whole over present cluelessness. I just don't see a way to enforce that. Thus for now I'll stick with over-demanding.
--JaroslavTulach 05:52, 28 August 2009 (UTC)
Contents |
Katie said ...
Anar said ...
Economists got on McCain and Hillary for their gas tax holiday, yet eyelalbing the images there seems to be a relationship (in most, but not all states) between taxes and prices.Why, then, would a gas tax holiday not lower retail pump prices? I'm assuming the tax is applied at the pump; if it's applied further up the chain, then I'd fully understand. Pump prices, though, are highly competitive. If it is charged higher up, then nevermind.
--Anar 11:04, 21 October 2013 (CEST)
Marry said ...
.INTERNAL READER:Amazon 16GB Class 10 SDHC #1Test finished wtihout errors.Writing speed: 15.1 MByte/sReading speed: 21.2 MByte/sAmazon 16GB Class 10 SDHC #2Test finished wtihout errors.Writing speed: 15.7 MByte/sReading speed: 21.3 MByte/sTranscend 16gb Class 10 SDHC #1Test finished wtihout errors.Writing speed: 16.6 MByte/sReading speed: 21.9 MByte/sTranscend 16gb Class 10 SDHC #2Test finished wtihout errors.Writing speed: 15.9 MByte/sReading speed: 20.3 MByte/sTranscend 8gb Class 10 SDHC #1Test finished wtihout errors.Writing speed: 17.7 MByte/sReading speed: 21.6 MByte/sTranscend 8gb Class 10 SDHC #2Test finished wtihout errors.Writing speed: 17.2 MByte/sReading speed: 21.3 MByte/s
--Marry 00:39, 22 October 2013 (CEST)
Melis said ...
and the black bar was in nearly every image.This card my be worth the glambe if you are shooting just for fun, but I would personally recommend purchasing cards from sandisk or lexar. Don't risk it!Like I said before, I love Amazon, but I find it necessary to leave an honest review.
--Melis 00:40, 22 October 2013 (CEST)
Martha said ...
Hi,Here's the truth: If you want to become a sccuessful forex trader, you must 1) Always stay humble Realize that at any given moment, you have the capacity to do serious and permanent damage to your forex account. In the blink of an eye, you can and will have your account wiped out if you are an undisciplined trader.2) Limit your risk Proper money management is the key to the long term survival of your account. Only risk a tiny percent of your account on any given trade( I usually risk 1-2% on any one trade). I recommend stop losses at all times. 3) Never be greedy Always take small gains and small losses. With discipline and training, you can easily learn to be profitable with a 50/50, or even lower, win/ loss ratio.4) Invest in your forex education Learn to be a good technical trader. Study pivot points, support, resistance, and trend lines. Through my own forex training, I've learned that all of the get rich quick systems and strategies will work one day, and not the next. Some are designed for trending markets while others work when the currencies are trading in a range. I've seen many accounts blown up from using a system that was touted as the latest and greatest'.There are quite a few forex training courses on the market. I've studied and reviewed many of them. As a matter of fact, I just finished studying a course called Forex Commander , which cost me $2000. There was a lot of great information in that course, but I still felt $2,000 was a little pricey. I've reviewed a couple of my favorite forex training courses at my site listed below. I also talk about how I lost $10,000 one time in less than 24 hours. It was a learning experience for sure.Hope this information helps,Dennis
--Martha 12:32, 23 October 2013 (CEST)
Windi said ...
I purchased this Bluetooth kreboayd to use with my Motorola Xoom (Android tablet), having read on a blog that it is indeed compatible. I have been using it for the last several days, and it is perfectly compatible.The range is perfectly acceptable, even in my office environment with lots of wireless devices running (any of which could potentially interfere, but thus far haven't)Normally I find curved kreboayds tricky to adjust to (with the more traditional inline kreboayd my usual weapon of choice), however this one accommodates my sausage fingers perfectly.On the Android at least, it is often difficult to get both the kreboayd itself, and the number pad to connect at the same time but this is an Android issue, as the two co-connect on Windows without argument.The ultra-slim profile is nice, though I've concluded that the only feature this kreboayd lacks is the ability to raise the top (as in, a collapsible stand). If this isn't a problem for you, then I highly recommend this product to anyone with a need for a Bluetooth (or generally cordless) kreboayd.If you don't particularly require a Bluetooth/cordless kreboayd, I'd suggest the Logitech G15.
--Windi 12:46, 23 October 2013 (CEST)
Ana said ...
I wish you health and happsneis every day!Ich wunsche Ihnen Gluck und Gesundheit jeden Tag!Je vous souhaite sante et bonheur chaque jour!
--Ana 13:12, 23 October 2013 (CEST)
Open said ...
many things in the phpipliines are cheaper than the USA prices but all electronics and electrical items like fans etc cost SO much more in most cases you could buy it in the usa and ship it there more cheaply. laptops fall into the latter category. even a cheap one with no memory and tiny hard drive you or i wouldn't even consider buying in the usa will cost you 2 to 3 times the US price for a good one. prices to ship things there can make the difference, and the customs list is often viewed as a shopping list by some unscrupulous postal corp employees en route, but if you're traveling there, definitely bring one along to save money. i priced one last year at $800 that i could buy here for $250. even a $14 20 fan from walmart costs over $60 there, but a fan from here wont work because you needs a 220v one. but most adapters for computers will now run off 220v as well as 110v so that's not a problem with them. there'll most likely be no power issue just read on the adapter and make sure it can also run on 220v. unlike Europe they use 60 cycles in the phpipliines like they USA you may also have to buy a smart buddy plug in wifi module that plugs into a usb port and have a sim card cell phone also far cheaper here to buy smart buddy loads for and transfer the time to the computer, as wifi isn't free in many places there, usually requiring you to pass a load to your computer to get on line. the good side to that IS the loads time you buy on a little smart buddy card are very cheap 300p roughly $6 And are available in most corner sari sari stores. and calling time there for smart COMMUNICATIONS is much cheaper than in the USA, but stay well clear of Globelines. they have weak unreliable signal and charge massive amounts and apparently can imprison philippine citizens for non payment of their exorbitant bills
--Open 13:37, 23 October 2013 (CEST)
Mark, I hope you don't mind, but I have a bleg for your readers....One of the thgins that I'd really like to do, but can't since I can't find an online application to make one, would be to make a county-by-county gas price cartogram (like the second picture), but one that subtracts state gas taxes from the price per gallon.I can find tools that are set up to make unique state-by-state cartograms, but not for the county-by-county maps. If anyone out there might know of such an application, please post a link!
--Katie 02:56, 21 October 2013 (CEST)