[R-SIG-Finance] Problem with RBloomberg retval argument

[Dirk Eddelbuettel]

On 19 January 2009 at 17:24, Sergey Goriatchev wrote:
| Hello everyone,
| 
| I have two issues that I want to ask.
|
| 1)
| I have problems with loading data with RBloomberg.
| More precisely, I do not seem to be able to load data into a data.frame.
| I get an error message:
| 
| start.date 	<- as.chron("1990-01-19")
| end.date	<- as.chron("2009-01-19")
| 
| conn <- blpConnect(show.days="week", na.action="na", periodicity="daily")
| 
| > bldata <- blpGetData(conn, c("ED4 Comdty", "ED12 Comdty"), "PX_LAST", start=start.date, end=end.date, retval="data.frame")
| Error in if (typ[n] == "character") { : argument is of length zero
| 
| What does that error message mean and what can I do to avoid this error message?

Your problem is not really in the assignment to bldata. Your problme is
indicated by the 'argument is of length zero': you didn't get any data from
Bloomberg.  You need to fix that first.  As a first guess, try a less
'greedy' retrieval.  You are unlikely to get 20 years of daily data in one
request.
 
| 2)
| If I load data from Bloomberg in matrix format, the date is converted
| to a number. For example:
| 
| > bldata <- blpGetData(conn, "ED4 Comdty", "PX_LAST", start=start.date, end=end.date, retval="matrix")
| > head(bldata)
|      [DATETIME] PX_LAST
| [1,]      32892   91.36
| [2,]      32895   91.37
| [3,]      32896   91.38
| [4,]      32897   91.38
| [5,]      32898   91.34
| [6,]      32899   91.28
| 
| I tried to convert the number to normal date and by trial and error I
| found the following:
| 
| > as.Date(32892, "1899-12-30")
| [1] "1990-01-19"
|
| Is it really true that count starts from December 30th 1899? Why?

Different offsets for 'the first known day' between different applications
and systems, eg Excel uses something very different from Unix etc.

Try return type 'zoo' instead of matrix -- zoo is a class that knows how to
deal with dates.  You may need to run    install.packages("zoo")   first.

Hope this helps, Dirk

-- 
Three out of two people have difficulties with fractions.