标签: commodity

什么是"商品软件"？(http://valgrind.org/docs/newsome2005.pdf文章中的部分标题)

(我不是英语演讲者,在我的语言中直接将"商品"翻译成软件对我来说没有多大意义.)

一个例子将不胜感激!

require("quantmod")

这有效:

#Symbol for Natural Gas in front month with Yahoo Finance
getQuote("NGH16.NYM", src="yahoo")

但这不"

getSymbols("NGH16.NYM", src="yahoo", from="2015-09-01")

    Error in download.file(paste(yahoo.URL, "s=", Symbols.name, "&a=", from.m,
  cannot open URL 'http://ichart.finance.yahoo.com/table.csv?s=NGF16.NYM&a=8&b=01&c=2015&d=11&e=24&f=2015&g=d&q=q&y=0&z=NGF16.NYM&x=.csv'
In addition: Warning message:
In download.file(paste(yahoo.URL, "s=", Symbols.name, "&a=", from.m,  :
  cannot open: HTTP status was '404 Not Found'

我如何获得价格历史记录？