Handling instrument symbols that clash or are not valid R names

Importing and Managing Financial Data in R

Joshua Ulrich

Quantitative Analyst & quantmod Co-Author and Maintainer

Syntactically valid names

Valid names contain letters, numbers, . and _
Must start with a letter, or a . followed by a non-number
May not be one of the reserved words
Not valid:
- .4times, _one, for

Accessing objects with non-syntactic names (1)

getSymbols() makes some names valid
- S&P 500 Index: "^GSPC"

getSymbols("^GSPC")

"GSPC"

head(GSPC, 3)

           GSPC.Open GSPC.High GSPC.Low GSPC.Close GSPC.Volume GSPC.Adjusted
2007-01-03   1418.03   1429.42  1407.86    1416.60  3429160000       1416.60
2007-01-04   1416.60   1421.84  1408.43    1418.34  3004460000       1418.34
2007-01-05   1418.34   1418.34  1405.75    1409.71  2919400000       1409.71

Accessing objects with non-syntactic names (2)

Some ticker symbols are not valid names
- Shanghai Stock Exchange Composite Index: "000001.SS"

getSymbols("000001.SS", auto.assign = TRUE)

"000001.SS"

str(000001.SS)

Error: unexpected symbol in "str(000001.SS)"

head(`000001.SS`, n = 3)

            000001.SS.Open   000001.SS.High     000001.SS.Low
2007-01-04         2715.72          2715.72           2715.72
2007-01-05         2641.33          2641.33           2641.33
2007-01-08         2707.20          2707.20           2707.20
           000001.SS.Close 000001.SS.Volume 000001.SS.Adjusted
2007-01-04         2715.72                0            2715.72
2007-01-05         2641.33                0            2641.33
2007-01-08         2707.20                0            2707.20

head(get("000001.SS"), n = 3)

            000001.SS.Open   000001.SS.High     000001.SS.Low
2007-01-04         2715.72          2715.72           2715.72
2007-01-05         2641.33          2641.33           2641.33
2007-01-08         2707.20          2707.20           2707.20
           000001.SS.Close 000001.SS.Volume 000001.SS.Adjusted
2007-01-04         2715.72                0            2715.72
2007-01-05         2641.33                0            2641.33
2007-01-08         2707.20                0            2707.20

Valid name for one instrument

Assign getSymbols() output to valid name
Convert column names to valid names

sse <- getSymbols("000001.SS", auto.assign = FALSE)

colnames(sse) <- paste("SSE", 
                         c("Open", "High", "Low", "Close",    
                           "Volume", "Adjusted"), sep = ".")
head(sse, n = 2)

            SSE.Open    SSE.High     SSE.Low
2007-01-04   2715.72     2715.72     2715.72
2007-01-05   2641.33     2641.33     2641.33
           SSE.Close  SSE.Volume  SSE.Adjusted
2007-01-04   2715.72           0       2715.72
2007-01-05   2641.33           0       2641.33

Create symbol-to-R object mapping with setSymbolLookup()

setSymbolLookup(SSE = list(name = "000001.SS"),
                  FORD = list(name = "F"))

getSymbols(c("SSE", "FORD"))

"SSE"  "FORD"

head(SSE, n = 2)

               SSE.Open  SSE.High  SSE.Low  SSE.Close  SSE.Volume  SSE.Adjusted
2007-01-04      2715.72   2715.72  2715.72    2715.72           0       2715.72
2007-01-05      2641.33   2641.33  2641.33    2641.33           0       2641.33

head(FORD, n = 2)

           FORD.Open  FORD.High FORD.Low  FORD.Close  FORD.Volume  FORD.Adjusted
2007-01-03      7.56     7.67       7.44       7.51      78652200       6.150263
2007-01-04      7.56     7.72       7.43       7.70      63454900       6.305862

Let's practice!

Importing and Managing Financial Data in R