Delete observations only if they meet two conditions

[Justin9]

Can someone help me out with some code that would delete observations where date="31Oct2022"d AND prev_date="31Mar2022"d (i.e. observation only deleted if BOTH conditions are true)?

Desired outcome: Delete observations only where date="31Oct2022"d AND prev_date="31Mar2022"d i.e. if only one condition met, keep observations e.g. date="29Apr2022"d / prev_date="31Mar2022"d because only one condition is met

When I run the code below, it  deletes observations where date="31Oct2022"d or prev_date="31Mar2022"d for some reason (e.g. in my example above, it deleted the three observations where date="29Apr2022"d / prev_date="31Mar2022"d)  - can someone suggest how I can edit my code to get my desired outcome please?

data test;
       set ac.information_values;
       where (date ne "31Oct2022"d and prev_date ne "31Mar2022"d);
run;

[PaigeMiller · Accepted solution]

Obvi a problem where the words of explanation don't match the code.

If your run the code shown and then "When I run the code below, it deletes observations where date="31Oct2022"d or prev_date="31Mar2022"d for some reason", I consider this impossible, either that's not the code, or your words are wrong.

Perhaps you could clear that up.

Anyway, what I *think* you want is this:

data test;
       set ac.information_values;
       if date="31Oct2022"d and prev_date="31Mar2022"d then delete;
run;

[Justin9]

Apologies, my code was supposed to be ne rather than =. Thanks for the code and help!