[R] fread transforms numbers

[William Dunlap]

Here is a way to reproduce the problem:
  > data.table::fread("9876543210\n") # number bigger than 2^31-1
                V1
  1: 4.879661e-314
and your work-around does fix things up
  > data.table::fread("9876543210\n", colClasses="numeric")
             V1
  1: 9876543210

Bill Dunlap
TIBCO Software
wdunlap tibco.com


On Wed, Mar 22, 2017 at 9:58 AM, Jeff Newmiller
<jdnewmil at dcn.davis.ca.us> wrote:
> You failed to provide a reproducible example, and you posted HTML so the quality of any answer will be limited by the quality of your question.
>
> My stab at your problem is that you should read ?fread, and in particular should try using the colClasses argument.
> --
> Sent from my phone. Please excuse my brevity.
>
> On March 22, 2017 8:52:55 AM PDT, Santosh <santosh2005 at gmail.com> wrote:
>>Hi
>>
>>I have been using "fread" utility of "data.table" packge .. on a
>>dataset of
>>about 20 million rows. It's a fantastic package to read datasets. Thank
>>you, Matt D.
>>
>>However, I am faced with a peculiar instance of  certain numbers in a
>>column being transformed.
>>
>>In the dataset, a column has values ranging from 1 to 9##########
>>(nchar(x)=11, e.g. 98765432109). After using "fread" to read the
>>dataset,
>>values in all the columns are displayed correctly upto the first 1000
>>rows.
>>If "fread" is applied for reading >1000 rows of  the total of 20Million
>>rows, the values in only this (column (having wide range of values) are
>>displayed as x.xxxxxxxe-3yy. (e.g. 3.5639877e-324)
>>
>>I tried reading all the columns as "character" and didn't help.
>>
>>Would highly appreciate your assistance!
>>
>>Thanks so much in advance.
>>
>>Best regards,
>>Santosh
>>
>>       [[alternative HTML version deleted]]
>>
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>>and provide commented, minimal, self-contained, reproducible code.
>
> ______________________________________________
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> and provide commented, minimal, self-contained, reproducible code.