Will attempt to locate price column(s) from a time series with rational defaults.
getPrice(x, symbol = NULL, prefer = NULL)A data object with columns containing data to be extracted
text string containing the symbol to extract
preference for any particular type of price, see Details
May be subset by symbol and preference.
prefer Preference will be for any commonly used financial time series price description,
e.g. 'trade', 'close', 'bid', 'ask' with specific tests and matching for types and column names
currently supported in R, but a default grep match will be performed if one of the supported types doesn't match.
The functionality was taken from the quantmod-package