[R] Read file

[Michael Bedward]

Hello Nilza,

If your file is small you can read it into a character vector like this:

indata <- readLines("foo.dat")

If your file is very big you can read it in batches like this...

MAXRECS <- 1000  # for example
fcon <- file("foo.dat", open="r")
indata <- readLines(fcon, n=MAXRECS)

The number of lines read will be given by length(indata).

You can check to see if the end of the file has been read yet with:
isIncomplete( fcon )

If a leading "*" character is a flag for the start of a station data
block you can find this in the indata vector with grepl...

start.pos <- which(indata, grepl("^\\s*\\*", indata)

When you're finished reading the file...
close(fcon)

Hope this helps,

Michael


On 3 October 2010 13:31, Nilza BARROS <nilzabarros at gmail.com> wrote:
> Dear R-users,
>
> I would like to know how could I read a file with different lines lengths.
> I need read this file and create an output to feed my database.
> So after reading I'll need create an output like this
>
> "INSERT INTO TEMP (DATA,STATION,VAR1,VAR2) VALUES (20100910,837460, 39,390)"
>
> I mean,  each line should be read. But I don`t how to do this when these
> lines have different lengths
>
> I really appreciate any help.
>
> Thanks.
>
>
>
> ====Below the file that should be read ===========
>
>
> *2010 10 01 00
> 83746  -43.25 -22.81      6  51*
> 1012.0  -9999    320     1.5   299.1   294.4 64
>  1000.0    114    250     4.1   298.4   294.8 32
>  925.0    797      0     0.0   293.6   292.9 32
>  850.0   1524    195     3.1   289.6   288.9 32
>  700.0   3156    290    11.3   280.1   280.1 32
>  500.0   5870    280    20.1   266.1   260.1 32
>  400.0   7570    265    23.7   256.6   222.7 32
>  300.0   9670    265    28.8   240.2   218.2 32
>  250.0  10920    280    27.3   230.2   220.2 32
>  200.0  12390    260    32.4   218.7   206.7 32
>  176.0  -9999    255    37.6 -9999.0 -9999.0  8
>  150.0  14180    245    35.5   205.1   196.1 32
>  100.0  16560    300    17.0   195.2   186.2 32
> *2010 10 01 00
> 83768  -51.13 -23.33    569  41
> * 1000.0     79  -9999 -9999.0 -9999.0 -9999.0 32
>  946.0  -9999    270     1.0   295.8   292.1 64
>  925.0    763     15     2.1   296.4   290.4 32
>  850.0   1497    175     3.6   290.8   288.4 32
>  700.0   3140    295     9.8   282.9   278.6 32
>  500.0   5840    285    23.7   267.1   232.1 32
>  400.0   7550    255    35.5   255.4   231.4 32
>  300.0   9640    265    37.0   242.2   216.2 32
>
>
> Best Regards,
>
> --
> Abraço,
> Nilza Barros
>
>        [[alternative HTML version deleted]]
>
>
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