Extract one element from yahooKeystats data
On Apr 27, 2009, at 8:16 PM, J Toll wrote:
On Mon, Apr 27, 2009 at 5:42 PM, David Winsemius <dwinsemius at comcast.net
wrote: Using str(data) would have been more informative. "data" it turns out is a dataframe with a single column. which is a factor with rownames. Not the most typical of constructions, but the authors must have had their reasons .... data$Value[row.names(data)=="Float"] # [1] 1.30B # 52 Levels: -1.00% -11.40% -18.69% -38.03% 0.04% 0.78 06-Feb-09 09- Mar-09 ... NA # ... or to get rid of those annoying factor levels... as.character(data[row.names(data)=="Float", ] ) # [1] "1.30B"
Thank you. I was in the middle of trying to respond to your first post when I got your second containing the answer. My problem is that I didn't understand the structure of the data and I couldn't figure out the relationship of the row names to the data so I was trying everything under the sun, yet nothing was yielding the results I wanted. On my own, I was able to retrieve the data using:
d.ibm$Value[38]
[1] 1.30B 52 Levels: -1.00% -11.40% -18.69% -38.03% 0.04% 0.78 06-Feb-09 09-Mar-09 1.176 1.30% 1.30B 1.32B 1.40% 1.7 10.304 100.84B ... NA But that seemed too brittle to be used reliably. I wanted a way to get to the data using what I now know to be the row name. I'm sorry my initial question was so vague/uninformative. Through brute force, I had tried dozens of different ways to coax out the information I needed. What I really needed was a better understanding of the data structure.
And this construction using indexing might be more natural: > data["Float", ] [1] 1.30B 52 Levels: -1.00% -11.40% -18.69% -38.03% 0.04% 0.78 06-Feb-09 09- Mar-09 ... NA > as.character( data["Float", ] ) [1] "1.30B" (I never have understood the attraction of factors. But there are a great many things I do not understand.) David Winsemius, MD Heritage Laboratories West Hartford, CT