topic Re: Help with filtering logic... in SAS Programming

Help with filtering logic...

NKormanik — Mon, 10 Jan 2022 06:44:21 GMT

Given A, B, C

In order for A to stay, it needs to be greater than either B or C.

If A is less than BOTH B and C, it gets tossed.

In SAS-speak, the following doesn't appear to be correct. Can someone please offer guidance?

if A < (B and C) then A = . ;

Using 'or' doesn't seem to work either.

Oh, and, these are numeric variables, numbers....

Hey, it's been a long day.

Re: Help with filtering logic...

KaueMAlmeida — Mon, 10 Jan 2022 04:21:13 GMT

I haven't tried this code, but it something like that...

If A < B or A < C then A = .;

If A gt B or A gt C then A = .;

Those variables are numerical? What kind of values do you have on each column? May you will have some problem when calculating the values.

Re: Help with filtering logic...

andreas_lds — Mon, 10 Jan 2022 07:44:55 GMT

In order for A to stay, it needs to be greater than either B or C.

Must be translated to the logic expression A > B or A > C.

If A is less than BOTH B and C

Means: A < B and A < C

Next step: what should happen if A = B and A = C?

And: why should A be set to missing if it should "stay"?

Re: Help with filtering logic...

Kurt_Bremser — Mon, 10 Jan 2022 10:37:46 GMT

if a > min(b,c);

Re: Help with filtering logic...

ballardw — Mon, 10 Jan 2022 16:25:49 GMT

@NKormanik wrote:

Given A, B, C

In order for A to stay, it needs to be greater than either B or C.

If A is less than BOTH B and C, it gets tossed.

In SAS-speak, the following doesn't appear to be correct. Can someone please offer guidance?
if A < (B and C) then A = . ;
Using 'or' doesn't seem to work either.

Oh, and, these are numeric variables, numbers....

Hey, it's been a long day.

It is "correct" in the way that SAS works. When you place a comparison in () such as (B and C) it evaluates that expression. Then returns the result of that expression as 1 (for true) or 0 for false. The comparison (B and C), since you use a Logic expression is testing "is B true and is C true". Which returns 1 when both are "true" or 0 if any are not "true". Values of 0 or missing are not "true".

Example:

data example;
   input b c;
   result = (b and c);
datalines;
1 1
0 1
. 1
. .
2 3
-4 5
6 7
1000000 .000004
;

So your code was asking, essentially, is "A <0" or is "A<1" depending on the values of B and C.

Re: Help with filtering logic...

NKormanik — Tue, 11 Jan 2022 19:40:58 GMT

Terrific, @Kurt_Bremser . How easy that was. Thanks!

Shows the great usefulness of max(), min(). And also, not().