topic Re: Use FIRSTOBS option in INFILE statement reading multiple files in SAS Programming

Use FIRSTOBS option in INFILE statement reading multiple files

deleted_user — Fri, 16 Apr 2010 10:55:19 GMT

Hi,
I need to read many text files from a directory into a one SAS data set.
All the text files have the same varibles but different number of observation.
I've tried to use a wildcard into the INFILE and the program works ok:

data pippo;
INFILE "C:\tmp\*.txt"
DLM=';' DSD missover FIRSTOBS=2;
input A
B
C
😧 $4.
E: $9.;
run;

The problem is that i have to read just since the second observation of every text file (becouse the first one are the titles), and if i use the FIRSTOBS option in the INFILE, it applies just for the first text file, but in the other one it reads all the obs.
Do you know how i could apply the FIRSTOBS =2 in every text file?

Thanks,
Elena

Re: Use FIRSTOBS option in INFILE statement reading multiple files

data_null__ — Fri, 16 Apr 2010 11:26:36 GMT

When reading with a wild card the files are treated as one stream. There is an option EOV to detect the start of a new file. You could test that variable and use programming logic to skip the first line of the file.

You CAN use FIRSTOBS when reading the files with the FILEVAR option. This requires creating a list of files to be read.

You should consult the documentation regarding the details of these INFILE statement options.

Re: Use FIRSTOBS option in INFILE statement reading multiple files

deleted_user — Fri, 16 Apr 2010 12:56:54 GMT

With the help of the option EOV i have got solve the problem

Thank you!

Re: Use FIRSTOBS option in INFILE statement reading multiple files

niemannk — Mon, 19 Apr 2010 15:57:13 GMT

I would be curious to see the result. The way I understand EOV is that it changes from 0 to 1 as soon as it encounters a new file. So reading in more than two files the EOV variable cannot tell you when you start reading in the third file. Or am I wrong?

Re: Use FIRSTOBS option in INFILE statement reading multiple files

Peter_C — Mon, 19 Apr 2010 16:38:28 GMT

niemannk

you're wrong

EOV is set when "reading after last record" occurs on any file and there is more data to follow, through "*" or file concatenation. So the EOV= flag is set after all files except the last.

PeterC

Re: Use FIRSTOBS option in INFILE statement reading multiple files

niemannk — Tue, 20 Apr 2010 07:35:40 GMT

ok. I played around with it and it looks like i need to reset the eov variable. sort of like this:

if _n_=1 or eov then do;
[...];
eov=0;
end;

Re: Use FIRSTOBS option in INFILE statement reading multiple files

data_null__ — Tue, 20 Apr 2010 12:18:39 GMT

The documentation is pretty clear on this one.

[pre]
EOV=variable
names a variable that SAS sets to 1 when the first record in a file in a series of
concatenated files is read. The variable is set only after SAS encounters the next
file. Like automatic variables, the EOV= variable is not written to the data set.

Tip: Reset the EOV= variable back to 0 after SAS encounters each boundary.
[/pre]