[Request] Provide an option to override fread's jumpiness

[franknarf1]

Reading this file with fread, I get ...

Error in fread("bah.csv") :
Internal error: Sampling jump point 10 is before the last jump ended

It would be nice to have an option to tell fread to traverse the file naively (or whatever), so I don't have to write a wrapper to catch this error and take it to read.csv.

Tested with...

data.table 1.10.5 IN DEVELOPMENT built 2017-05-09 05:01:26 UTC; travis

R version 3.3.3 (2017-03-06)
Platform: x86_64-w64-mingw32/x64 (64-bit)
Running under: Windows 10 x64 (build 14393)

locale:
[1] LC_COLLATE=English_United States.1252  LC_CTYPE=English_United States.1252   
[3] LC_MONETARY=English_United States.1252 LC_NUMERIC=C                          
[5] LC_TIME=English_United States.1252    

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base     

other attached packages:
[1] data.table_1.10.5

loaded via a namespace (and not attached):
[1] tools_3.3.3

[artemklevtsov]

Same here with this file: test2.zip

R> fread("/tmp/test2.csv", verbose = TRUE)
Input contains no \n. Taking this to be a filename to open
NAstrings = [<<NA>>]
None of the NAstrings are numeric (such as '-9999').
`filename` argument given, attempting to open a file with such name
File opened, size 0.000100 GB.
Memory mapping ... ok
Detected eol as \n only (no \r afterwards), the UNIX and Mac standard.
Positioned on line 1 starting: <<X1,X2,X3,X4,X5,X6,X7,X8,X9,X10>>
Detecting sep ...
  sep==','(ascii 44)  with 100 lines of 11 fields using quote rule 0
Detected 11 columns on line 1. This line is either column names or first data row (first 30 chars): <<X1,X2,X3,X4,X5,X6,X7,X8,X9,X10>>
All the fields on line 1 are character fields. Treating as the column names.
Number of sampling jump points = 11 because 107192 bytes from row 1 to eof / (2 * 3065 jump0size) == 17
Type codes (jump 000)    : 62222222222  Quote rule 0
Type codes (jump 001)    : 65555555555  Quote rule 0
Ошибка в fread("/tmp/test2.csv", verbose = TRUE) :
  Internal error: Sampling jump point 10 is before the last jump ended

R> sessionInfo()
R version 3.4.0 (2017-04-21)
Platform: x86_64-pc-linux-gnu (64-bit)
Running under: Arch Linux

Matrix products: default
BLAS/LAPACK: /usr/lib/libopenblas_haswellp-r0.2.19.so

locale:
 [1] LC_CTYPE=ru_RU.UTF-8       LC_NUMERIC=C               LC_TIME=ru_RU.UTF-8        LC_COLLATE=C              
 [5] LC_MONETARY=ru_RU.UTF-8    LC_MESSAGES=ru_RU.UTF-8    LC_PAPER=ru_RU.UTF-8       LC_NAME=C                 
 [9] LC_ADDRESS=C               LC_TELEPHONE=C             LC_MEASUREMENT=ru_RU.UTF-8 LC_IDENTIFICATION=C       

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base     

other attached packages:
[1] data.table_1.10.5

loaded via a namespace (and not attached):
[1] compiler_3.4.0 tools_3.4.0    parallel_3.4.0 yaml_2.1.14