topic Re: use dlm and dsd in New SAS User

use dlm and dsd

anming — Mon, 04 Jan 2021 16:21:40 GMT

For an external file employee.txt like:

susan*12/29/1970*10
micheal**6

data employee;
infile "/special path/employee.txt" dlm='*' dsd;
input employee $ bdate: mmddyy10. years;
run;

both dlm and dsd are needed for proper input. However, there is no comma in the input data but only two stars for a missed value. Why is a dsd required? I read a few documents and posters. It seems it is still confused.

Re: use dlm and dsd

ballardw — Mon, 04 Jan 2021 16:30:40 GMT

DSD is required to treat two consecutive delimiters as a missing value as well as to allow the delimiter characters to appear as part of a value inside quoted text. Without the DSD option list input as you are using will treat consecutive delimiters as a single delimiter and the values would be read incorrectly.

The explicit DLM is going to be needed since you apparently have a character other than the comma as the delimiter. Comma is the default delimiter.

Re: use dlm and dsd

Tom — Mon, 04 Jan 2021 17:05:41 GMT

The default is to use space as the delimiter and to treat multiple delimiters as one. That makes sense when space is the delimiter because you normally use multiple spaces to make the data columns align for when humans view the file. To treat adjacent delimiters as marking a missing value you need the DSD option. But when you use the DSD option the default delimiter is now going to be a comma instead of space. So to use asterisk instead of comma you need to use the DLM option to override the default delimiter. Note that the DSD option will also change how quotes are treated. Quotes around values are removed and any delimiter enclosed in quotes is treated as part of the data and not as a delimiter.