>>>>> "Herve" == Herve Pages <[EMAIL PROTECTED]>
>>>>> on Fri, 03 Nov 2006 10:50:10 -0800 writes:
Herve> Hi Martin,
Herve> Thanks for the answer!
Herve> OK I can use data.matrix to convert a data frame to a numeric
Herve> matrix but that's another story. Basically I'm reporting 2
Herve> problems with 'as.matrix' when applied to a data frame:
yes, indeed, and I was missing them up partly.
Herve> 1) A documentation problem:
Herve> "The method for data frames will convert any
Herve> non-numeric/complex column into a character vector
Herve> using 'format'"
>> df5 <- data.frame(toto=c("a","bb"), titi=c(9,999))
>> as.matrix(df5)
Herve> toto titi
Herve> 1 "a" " 9"
Herve> 2 "bb" "999"
Herve> As I said, it seems to be the other way around: it's not the
Herve> "non-numeric" column that is converted to a character vector,
Herve> it's the "numeric" column.
Indeed, and I now agree that the documentation is more wrong
than I first acknowledged. I'm changing it currently.
Herve> 2) the questionable decision to do this conversion using 'format'
Herve> (leading to the addition of unnecessary white space) and not
Herve> simply 'as.character'
as Bill remarked,
- there were good reasons pro such a decision,
- to change such decisions without necessity is a problem for
back-compatibility
Herve> BTW your mailer seems to do some strange reformatting to the output
Herve> of my code snippets making it hard to see the "formatting" problem
Herve> that I'm trying to show.
yes. Part of it was my mistake; sorry.
Best regards to Seattle,
Martin
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