setSymbolLookup: Manage Symbol Lookup Table

Description

Create and manage Symbol defaults lookup table within R session for use in getSymbols calls.

Usage

setSymbolLookup(...)
getSymbolLookup(Symbols=NULL)
saveSymbolLookup(file,dir="")
loadSymbolLookup(file,dir="")

Arguments

...

name=value pairs for symbol defaults

Symbols

name of symbol(s)

file

filename

dir

directory of filename

Value

Called for its side effects, the function changes the options value for the specified Symbol through a call to options(getSymbols.sources=...)

Details

Use of these functions allows the user to specify a set of default parameters for each Symbol to be loaded.

Different sources (e.g. yahoo, MySQL, csv), can be specified for each Symbol of interest. The sources must be valid getSymbols methods - see getSymbols for details on which methods are available, as well as how to add additional methods.

The argument list to setSymbolLookup is simply the unquoted name of the Symbol matched to the desired default source, or list of Symbol specific parameters.

For example, to signify that the stock data for Sun Microsystems (JAVA) should be downloaded from Yahoo! Finance, one would call setSymbolLookup(JAVA='yahoo') or setSymbolLookup(JAVA=list(src='yahoo'))

It is also possible to specify additional, possibly source specific, lookup details on a per symbol basis. These include an alternate naming convention (useful for sites like Yahoo! where certain non-traded symbols are prepended with a caret, or more correctly a curcumflex accent. In that case one would specify setSymbolLookup(DJI=list(name="^DJI",src="yahoo"))) as well as passed parameters like dbname and password for database sources. See the specific getSymbols function related to the source in question for more details of each implementation.

If a single named list is passed into the function without naming the list as a parameter, the names of this list will be presumed to be symbol names to be added to the current list of symbols.

All changes are made to the current list, and will persist only until the end of the session. To always use the same defaults it is necessary to call setSymbolLookup with the appropriate parameters from a startup file (e.g. .Rprofile) or to use saveSymbolLookup and loadSymbolLookup to save and restore lookup tables.

To unset a specific Symbol's defaults, simply assign NULL to the Symbol.

Examples

Run this code

setSymbolLookup(QQQQ='yahoo',DIA='MySQL')
getSymbolLookup('QQQQ')
getSymbolLookup(c('QQQQ','DIA'))

## Not run: 
# ## Will download QQQQ from yahoo
# ## and load DIA from MySQL
# getSymbols(c('QQQQ','DIA'))
# ## End(Not run)

## Use something like this to always retrieve
## from the same source

.First <- function() {
  require(quantmod,quietly=TRUE)
  quantmod::setSymbolLookup(JAVA="MySQL")
}

## OR

saveSymbolLookup()
loadSymbolLookup()