topic Re: convert chracter to nmeric and remove letters in SAS Programming

convert chracter to nmeric and remove letters

lillymaginta — Mon, 10 Sep 2018 14:40:43 GMT

data have;
input $ drug;
cards;
25 mg
12 mg
13 mg; 
Run;

I need to create a new data that convert the chracter variable drug to numeric including only the numeric portion of the variable

output

drug

Thanks

Re: convert chracter to nmeric and remove letters

RW9 — Mon, 10 Sep 2018 14:47:05 GMT

data have;
 infile datalines dlm=",";
 input drug $;
 want=input(compress(drug,,'kd'),best.);
datalines;
25 mg
12 mg
13 mg
; 
run;

The compress 'kd' option means keep digits.

Re: convert chracter to nmeric and remove letters

lillymaginta — Mon, 10 Sep 2018 14:49:44 GMT

Thank you RW9 for the prompt response!

Re: convert chracter to nmeric and remove letters

FreelanceReinh — Mon, 10 Sep 2018 16:13:19 GMT

@lillymaginta:

Make sure to adapt the suggested code if your data contain non-integer values such as "12.5 mg". Otherwise the numeric dose will be wrong (like 125 in my example) because the decimal point will be deleted.

You could, for example, list all characters to be deleted in the second argument of the COMPRESS function:

want=input(compress(drug,'gmµu'),best.);

This would correctly transform values including a decimal point and still remove units "mg", "g", "ug" or "µg".

Re: convert chracter to nmeric and remove letters

data_null__ — Mon, 10 Sep 2018 17:17:57 GMT

@FreelanceReinh wrote:

@lillymaginta:

Make sure to adapt the suggested code if your data contain non-integer values such as "12.5 mg". Otherwise the numeric dose will be wrong (like 125 in my example) because the decimal point will be deleted.

You could, for example, list all characters to be deleted in the second argument of the COMPRESS function:
want=input(compress(drug,'gmµu'),best.);
This would correctly transform values including a decimal point and still remove units "mg", "g", "ug" or "µg".

Might be easier to add the decimal indicator to the list of Kept characters.

input(compress(drug,'.','kd'),12.);

Re: convert chracter to nmeric and remove letters

ChrisHemedinger — Mon, 10 Sep 2018 17:56:08 GMT

@lillymaginta I was about to edit the topic title to fix spelling...but then I SEE WHAT YOU DID THERE. 😉

Re: convert chracter to nmeric and remove letters

FreelanceReinh — Mon, 10 Sep 2018 18:02:05 GMT

Thanks @data_null__ for chiming in. I had considered this option, too, but I was thinking that the period might occur in abbreviations (like "gr."). In this case, however, COMPRESS alone wouldn't work anyway (unlike SCAN, PRXCHANGE, ...).

Re: convert chracter to nmeric and remove letters

data_null__ — Mon, 10 Sep 2018 18:22:41 GMT

@FreelanceReinh yes there are many possibilities that are not being accounted for. Using SCAN with those same options accounts for your latest scenario.

Re: convert chracter to nmeric and remove letters

FreelanceReinh — Mon, 10 Sep 2018 18:39:46 GMT

Good point. Cases like "15mg" or "0.5g" are treated correctly as well.

Re: convert chracter to nmeric and remove letters

lillymaginta — Tue, 11 Sep 2018 16:17:34 GMT

Thank you data_null, the prior code resulted in large unexpected numbers, I appreciate the follow-up.

Re: convert chracter to nmeric and remove letters

data_null__ — Tue, 11 Sep 2018 19:47:18 GMT

@lillymaginta wrote:

Thank you data_null, the prior code resulted in large unexpected numbers, I appreciate the follow-up.

Not sure what you're talking about. What prior code? What unexpected numbers?