[R] converting a character matrix into numeric....

[akshay kulkarni]

Dear members,
                            I have an xts object:

> head(INFYTX)
           INFY Historical Data INFY Historical Data.1 INFY Historical Data.2
2003-04-16 "47.26"              "44.28"                "47.56"
2003-04-17 "46.30"              "44.92"                "46.53"
2003-04-21 "45.82"              "47.27"                "47.50"
2003-04-22 "45.62"              "46.06"                "46.16"
2003-04-23 "45.05"              "46.28"                "46.50"
2003-04-24 "45.28"              "44.80"                "46.84"
           INFY Historical Data.3 INFY Historical Data.4
2003-04-16 "44.28"                "1805267"              "5.77%"
2003-04-17 "44.06"                "1536300"              "-2.03%"
2003-04-21 "45.63"                "887774"               "-1.04%"
2003-04-22 "44.73"                "944036"               "-0.44%"
2003-04-23 "44.77"                "759898"               "-1.25%"
2003-04-24 "44.53"                "1185402"              "0.51%"

But it is populated with character values and I want to convert them to numeric. THe following code doesn't work:

> head(coredata(INFYTX))
     INFY Historical Data INFY Historical Data.1 INFY Historical Data.2 INFY Historical Data.3
[1,] "47.26"              "44.28"                "47.56"                "44.28"
[2,] "46.30"              "44.92"                "46.53"                "44.06"
[3,] "45.82"              "47.27"                "47.50"                "45.63"
[4,] "45.62"              "46.06"                "46.16"                "44.73"
[5,] "45.05"              "46.28"                "46.50"                "44.77"
[6,] "45.28"              "44.80"                "46.84"                "44.53"
     INFY Historical Data.4
[1,] "1805267"              "5.77%"
[2,] "1536300"              "-2.03%"
[3,] "887774"               "-1.04%"
[4,] "944036"               "-0.44%"
[5,] "759898"               "-1.25%"
[6,] "1185402"              "0.51%"

> class(coredata(INFYTX))
[1] "matrix" "array"
> class(coredata(INFYTX)) <- "numeric"
Warning message:
In class(coredata(INFYTX)) <- "numeric" : NAs introduced by coercion
> class(coredata(INFYTX))
[1] "matrix" "array"
> head(coredata(INFYTX))
     INFY Historical Data INFY Historical Data.1 INFY Historical Data.2 INFY Historical Data.3
[1,] "47.26"              "44.28"                "47.56"                "44.28"
[2,] "46.3"               "44.92"                "46.53"                "44.06"
[3,] "45.82"              "47.27"                "47.5"                 "45.63"
[4,] "45.62"              "46.06"                "46.16"                "44.73"
[5,] "45.05"              "46.28"                "46.5"                 "44.77"
[6,] "45.28"              "44.8"                 "46.84"                "44.53"
     INFY Historical Data.4
[1,] "1805267"              NA
[2,] "1536300"              NA
[3,] "887774"               NA
[4,] "944036"               NA
[5,] "759898"               NA
[6,] "1185402"              NA

Why is the coredata matrix not changing to numeric when the class is changed to numeric? How else to convert coredata into numeric?

THanking you,
Yours sincerely,
AKSHAY M KULKARNI

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