o****o
发帖数: 8077 | 1 借帖问如何高效读入大的CSV或者任意TXT文件
比如读入一个700多MB的CSV，在r里面很慢，即使是用如下方式先预置了每列的属性：
trainset<-read.csv("train_set.csv", nrows=1000)
colClasses<-sapply(trainset, class);
trainset<-read.csv("train_set.csv", sep=",", header=T,
colClasses=colClasses)
仍然要花很长时间，差不都是SAS的30倍，SAS一分钟，R硬是花了30多分钟。 |
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b*****e
发帖数: 5476 | 3 CRH3原型车是西门子Velaro E，本来就是按350设计的，跑西班牙马德里到巴塞的线路
。拿这个骂刘志军基本就两种可能，要么是一窍不通，要么就是欲加之罪啊
西门子官网
http://www.siemens.com/press/en/presspicture/?press=/en/pp_ts/2
In the future the Spanish National Railway Renfe will operate the Siemens Velaro high-speed trainset (named AVE S 103) at a regular speed of 350 km/h. |
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a*****7
发帖数: 342 | 4 既然如此，原来提高到350根本就不是我们自己的技术，又是买来，贴上自己的标签。
Velaro high-speed trainset (named AVE S 103) at a regular speed of 350 km/h. |
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t******t
发帖数: 3045 | 5 it will be 350 in the future, not now
Velaro high-speed trainset (named AVE S 103) at a regular speed of 350 km/h. |
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c**i
发帖数: 6973 | 6 (1) Evan Ramstad, Shipyards Running Aground; Recession's lagging effect on
orders forces South Korean shipbuilders to cut payrolls, shift course. Wall
Street Journal, June 23, 2011
http://online.wsj.com/article/SB100014240527
02304778304576375972346103698.html
Quote:
"The downturn is affecting shipyards world-wide. China's shipbuilding
association last month said some of the country's yards would suspend
production after completing existing orders.
"Ships are the country's [Korea's] biggest expo... 阅读全帖 |
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o******r
发帖数: 1378 | 7 From Wikipedia
Acela Express trains are the only true high-speed trainsets in North America
; the highest speed they attain is 150 mph (240 km/h), though their average
is less than half that speed.
基本上是中国2000年的水平 |
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t****z
发帖数: 8931 | 8 加拿大73%服务业
制造业是小头
但是美国通用、福特、克莱斯勒三大汽车公司在安大略设厂，高产量汽车
加拿大庞巴迪在美国设4个厂，雇佣10，000美国人造支线飞机和火车车厢运输设备
庞巴迪向美国出口纽约地铁，达拉斯，迈阿密，洛杉矶，西雅图，明尼阿波利斯双层车
厢，旧金山，丹佛，休斯顿，匹兹堡，西雅图，亚特兰大等等机场列车
20 high-speed trainsets for the Amtrak Acela Express service (the first and
only high speed trains in North America)
More than 1,800 subway cars in service at New York City Transit
More than 1,100 electric multiple unit commuter cars serving New York and
Connecticut on the Long Island Rail Road and Metro-North Railroad
Hundreds of alumin... 阅读全帖 |
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g**********y
发帖数: 14569 | 10 ToysRus的那个Imaginarian的trainset， 连table带附件，火车，等等，一套就$129,
买一套什么都有了。比正宗Thomas的设计还复杂，Thomas那套的也能在上面玩。 |
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z*********i
发帖数: 37 | 11 从TOYSRUS原价$180买的，非常结实漂亮的火车桌子和超过100多PIECES的TRAINSETS.
还有两个非常大的抽屉，有会发声的隧道等。
是小男孩必备玩具，可以让他着迷很久，也是小孩PLAYDATE超好的玩具。
现低价$80出售，实在是需要藤地方。地址在牛顿市，还可以赠送其他牌子的火车玩具。
有兴趣者请速回信。谢谢 |
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s*******s
发帖数: 9926 | 12 根据路透社的报导 中国已经递交意愿书了 而且强调技术和经验是在领先世界的状况 (
帮忙翻译一下好了 随便google就有的东西)
CNR, its unit Tangshan Railway and U.S.-based SunGroup USA are submitting an
expression of interest to California's $68 billion high-speed rail project
for a contract to supply up to 95 trains that can travel as fast as 354
kilometers per hour (221 miles per hour), SunGroup told Reuters.
"We believe that high-speed rail is something that China does very well, and
it's a product that we can export across the world," SunGroup spokesm... 阅读全帖 |
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