[R] retaining characters in a csv file
r.turner at auckland.ac.nz
Wed Sep 23 03:26:58 CEST 2015
On 23/09/15 11:19, peter dalgaard wrote:
>> On 23 Sep 2015, at 00:33 , Rolf Turner <r.turner at auckland.ac.nz> wrote:
> [read.csv() doesn't distinguish "123.4" from 123.4]
>> IMHO this is a bug in read.csv().
> Dunno about that:
> pd$ cat ~/tmp/junk.csv
> pd$ open !$
> open ~/tmp/junk.csv
> And lo and behold, Excel opens with
> 1 1
> 2 2
> and all cells numeric.
I would say that this phenomenon ("Excel does it") is *overwhelming*
evidence that it is bad practice!!! :-)
> I don't think the CSV standard (if there is one...) specifies that
> quoted strings are necessarily text.
Duncan Murdoch has pointed out that this is definitely *not* the case.
> I think we have been here before, and found that even if we decide
> that it is a bug (or misfeature), it would be hard to change, because
> the modus operandi of read.* is to first read everything as character
> and _then_ see (in type.convert()) which entries can be converted to
> numeric, logical, etc.
As Arunkumar Srinivasan has pointed out, fread() from the data.table
package can handle this, so it is *not impossible*.
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