topic Re: SCAN and STR Function in SAS Studio

SCAN and STR Function

kcvaldez98 — Mon, 23 Oct 2023 19:00:55 GMT

I am trying to extract the lower bounds of a 95% CI from a character string and I am trying to extract the number while making it numeric.

The character string I am extracting from is "95% C.I.: 7.7 - 10.7" I am trying to just keep the 7.7 and make it numeric.

The code I put in is:

DATA WORK.CI;

SET OLD DATA;

countylowerCI = SUBSTR(SCAN(countyCI, 1, ':-'));

RUN;

What am I doing wrong?

Re: SCAN and SUBSTR Function

PaigeMiller — Mon, 23 Oct 2023 19:10:46 GMT

@kcvaldez98 wrote:

countylowerCI = SUBSTR(SCAN(countyCI, 1, ':-'));

Does this help you figure it out?

data a;
    countyci="95% C.I.: 7.7 - 10.7";
    word1=scan(countyCI, 1, ':-');
    word2=scan(countyCI, 2, ':-');
    word3=scan(countyCI, 3, ':-');
run;

The above code does not return a numeric value, it returns a character string, but I'm guessing you make that change after you figure it out.

Why are you getting confidence intervals as text strings? All SAS procedures can get the actual numerical value as output, that's a much better way to go.

Re: SCAN and STR Function

Reeza — Mon, 23 Oct 2023 19:08:01 GMT

Use INPUT to convert a character variable to numeric, not sure what is the purpose of SUBSTR.

lowerCI = input(scan(countyCI, 2, ':-'), best12.);

Note that I would recommend running the scan function first to verify what it's returning for your text and then try the conversion.

Re: SCAN and STR Function

antonbcristina — Mon, 23 Oct 2023 19:12:38 GMT

As suggested, do this in stages. First scan the character string, confirming you have the right number (as a character string), then convert it using the INPUT function.

DATA CI;
	countyCI = "95% C.I.: 7.7 - 10.7";
	countylowerCI_char = SCAN(countyCI, 2, ':-');
	countylowerCI_num  = input(countylowerCI_char,best10.);
RUN;