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哪位大哥帮忙翻译下啊 Developing geographic applications is far more complicated than itshould be. I have several goals for this book. The first is to demystifygeographic information systems (GIS) and teach you a bit of the lingo.The second goal is to help you download some free data and learn aprogrammatic API or two. These lead to the final goal of turning youinto a GIS developer.Demystifying GISMany popular websites have GIS underpinnings (and you don’t need aPhD to use them). MapQuest1 is perhaps one of the most well known.In the late 1990s, it virtually owned the online mapping market.In the following years, additional players joined the game. All the majorsearch engines now have GIS offerings. For example, take a look atGoogle Maps.2 You simply enter a street address, and it shows you thelocation on a map. Yahoo3 and MSN4 offer similar functionality.Although all these sites provide a valuable service, they do little to raisethe geographic literacy of the general public. I can’t criticize them toomuch for this—I’m sure that ease of use was their primary design goal.But by shielding us from the complexity of the GIS problems they solve,they don’t help us build GIS solutions of our own. They are “blackboxes” of geographical wonder.Similarly, most consumer-grade global positioning system (GPS) devicesare sold as black boxes as well. In-dash GPS is fast becoming the derigueur option in high-end automobiles, but most drivers would nomore consider customizing them than they would try to change thesound of their horn or the wiring of their radio.I am not suggesting that everyone who drives a car should be a mechanic,or even want to be. But for those of us who are just the slightestbit curious, it would be nice to be able to crack open the hood and pokearound. Maybe I’ve just been spoiled by my years as a web developer.When I come across a cool website, I can not only appreciate it as anend user but also choose View > Source to see how it was put together.To me, this is the best of all worlds—let it be a black box to those whodon’t care to look any further, but also cater to those who want to liftup the corner and nose around the insides a bit. I firmly believe thatthis democratic approach to the technology is one of the primary forcesbehind the Web’s rapid growth and widespread adoption.Unfortunately, this do-it-yourself, learn-from-others gestalt is missingfrom the GIS examples we’ve discussed so far. The fact that there isn’t ababy step up to the next level of difficulty only compounds the problem.There seems to be very little middle ground when it comes to complexityin GIS applications. Compared to MapQuest, programs that exposetheir GIS underpinnings are a giant leap up in terms of complexity. Thegood news is even with just a little bit of industry knowledge, you canput together some impressive results with the free tools and data outthere.So, regarding my first goal for the book, the “blithely ignorant end user”segment and the “all-knowing industry veteran” segment are both well
问个问题啊？ 3次函数求根怎么求啊，我指的是普遍的3次函数，不是指那些特殊的。
求助：上（下）确界的问题 定理：有上（下）界的数集必有上（下）确界这个定理，在数学分析里面，是以“单调有界数列必有极限”为前提证明的。这个我已经实现了。有没有其他证明方法？？？？？？？？因为《数学分析》（陈传璋版）里面提到，这条定理是可以用实数理论严格证明的。
问个问题啊 现在在哪可以看到尤文的比赛啊吧主可不可以整理下给个？？？
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