[R] colnames from read.table

[Erik Iverson]

Chua Siang Li wrote:
>    Hi.  May I know why the colnames is NULL when reading only 1 column from a
>    csv file?  

You are not "reading only 1 column from a csv file", you are subsetting 
one column of a data.frame.  See ?Extract and the "drop" argument 
specifically.

How do I get the colname then?

?names in this case.  Always know the class of the object you are 
dealing with, and which methods are defined for that class.

?class, ?methods


See
  Thanks.
>    > xy = read.table("dataFile.csv",header=T, sep=",")
>    > y <- xy[,1]
>    > xDate <- xy[,2]
>    > x <- xy[,3:8]
>    > colnames(y)
>    NULL
>    > colnames(xDate)
>    NULL
>    > colnames(x)
>    [1]    "Market.Price"    "Quantity"        "Country"        "Incoterm"
>    "Channel"
>    [6] "PaymentTerm"
>    ----
>    Chua Siang Li
>    Consultant - Operations Research
>    Acceval Pte Ltd
>    Tel: 6297 8740
>    Email: siang.li.chua at acceval-intl.com
>    Website: www.acceval-intl.com
>    This message and any attachments (the "message"...{{dropped:12}}
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