topic Re: Help with inputting character variables with different lengths in SAS Programming

Help with inputting character variables with different lengths

hhchenfx — Fri, 31 Jan 2014 23:03:47 GMT

Hello Everyone,

I have problem reading the following character variables with varies length.

data cond1;

input name $ value;

datalines;

december_12_2013 -1

medium_length -1

short 3

;;run;

I try to use format name $30. but it read the value as part of the character.

Please help me with that one.

Thank you and have a nice weekend.

HHC

Re: Help with inputting character variables with different lengths

Cynthia_sas — Sat, 01 Feb 2014 00:25:19 GMT

Hi,
The default length for character variables that you read will be 8 characters in length. The FORMAT won't do you any good. You need a simple LENGTH statement or an INFORMAT statement. If you don't understand why you need a LENGTH statement or an INFORMAT statement, I would suggest that you read the doc. There is a 3rd method too, that is to use an informat colon modifier in the INPUT statement. See the code below. I added SUPERCALIFRAGILISTICEXPEALIDOCIOUS to the data just for fun.

Cynthia

ods _all_ close;

** Method A;

data cond1_a;
length name $35;
input name $ value;
datalines;
december_12_2013 -1
medium_length -1
short 3
supercalifragilisticexpealidocious 10
;
run;

ods listing;
proc print data=cond1_a;
title 'A) use LENGTH statement';
run;

** Method B;

data cond1_b;
informat name $35.;
input name $ value;
datalines;
december_12_2013 -1
medium_length -1
short 3
supercalifragilisticexpealidocious 10
;
run;

ods listing;
proc print data=cond1_b;
title 'B) use INFORMAT statement';
run;

** Method C;

data cond1_c;
input name : $35. value;
datalines;
december_12_2013 -1
medium_length -1
short 3
supercalifragilisticexpealidocious 10
;
run;

ods listing;
proc print data=cond1_c;
title 'C) use INFORMAT modifier in INPUT statement';
run;

Re: Help with inputting character variables with different lengths

hhchenfx — Sat, 01 Feb 2014 02:12:48 GMT

Thank you, Cynthia.

Actually, I tried Method 1 before but instead, I put the Length after Input and it does not work.

That's weird.

Everything is good now.

Thank you again.

HHC

Re: Help with inputting character variables with different lengths

Tom — Sat, 01 Feb 2014 03:17:31 GMT

SAS will define a variable based on what it knows the first time it sees it. That is why when you put the LENGTH statement after the INPUT statement it did not have any effect because SAS already had to guess what length to use when it compiled the INPUT statement.

It is best to define your variables explicitly with a LENGTH or ATTRIB statement. Once they are defined then your input statement can then be much simpler.

data cond1;

length name $30 value 8 ;

input name value;

datalines;

december_12_2013 -1

medium_length -1

short 3

;;;;

Re: Help with inputting character variables with different lengths

hhchenfx — Sat, 01 Feb 2014 18:51:23 GMT

Thanks, Tom, for clear explanation.

HHC