topic Re: unknown variable name and conversion to numeric in SAS Procedures

unknown variable name and conversion to numeric

Nikos — Wed, 18 Apr 2012 12:19:59 GMT

Hi,

I have a macro that calls several data sets at certain step i use a proc transpose that creates a new variable as follows CNT_&STATE with &STATE (macro variable)and taking values like AON, KAT etc. depending on the input of the initial data set used.

Subsequently the output data set of the proc transpose is further developed but at this stage I would like to:

a) check whether var CNT_&STATE is a character or numeric var

b) if it is character var then to change it to numeric

Any suggestions more than welcome

Thank you in advance

Best regards

Nikos

Re: unknown variable name and conversion to numeric

Linlin — Wed, 18 Apr 2012 12:42:15 GMT

do you want to try something like below? you can convert it to numeric without knowing it is a character or numeric variable.

data have;

input a$ b;

_a=a*1;_b=b*1;

cards;

1 2

2 3

;

proc contents data=have;run;

Linlin

Re: unknown variable name and conversion to numeric

Astounding — Wed, 18 Apr 2012 13:07:42 GMT

And to end up with the same names you started with:

data have (drop=a b rename=(_a=a _b=b);

This approach can give you notes in the log about character to numeric conversion. If those notes are troublesome to you, there are more complex ways to solve the problem.

Re: unknown variable name and conversion to numeric

data_null__ — Wed, 18 Apr 2012 14:35:59 GMT

It would be easier to check the variable being transposed and convert it to numeric before it is transposed. Then there is no rename issue. Post some sample data and I will show you what I'm thinking about.

Re: unknown variable name and conversion to numeric

Ksharp — Thu, 19 Apr 2012 02:30:05 GMT

There is a function you can use to check whether it is character or numeric.

array x(4) x1-x4;

y=vtype(x(1));

put y=;

Ksharp

Re: unknown variable name and conversion to numeric

Haikuo — Thu, 19 Apr 2012 12:28:07 GMT

Excellent idea, but with a little confusing example, as you should already know the variable type of your array members before you can define them.

data _null_;

c='c';

n=1;

tc=vtype(c);

tn=vtype(n);

put 'tc=' tc 'tn=' tn;

run;

Regards,

Haikuo

Re: unknown variable name and conversion to numeric

byronk — Thu, 19 Apr 2012 13:58:20 GMT

try something like this....

data have;

cnt_sc=1;

cnt_nc="1";

cnt_ga="1";
cnt_fl=1;

output;

run;

proc contents data=have out=_type noprint;run;

procsql noprint;

select
name,

"_"||strip(name),

"_"||strip(name)||"="||strip(name)

into
:cntChar separated by " ",

:NcntChar separated by" ",

:RcntChar separated by" "

from _type wheretype=2;

quit;

%put &RcntChar;

data want(drop=&cntChar rename=(&RcntChar));

set have;

array _c &cntChar;

array _n &NcntChar;

do over _c;

_n=input(_c,8.);

end;

run;

proc contentsdata=want; run;

Re: unknown variable name and conversion to numeric

eirhpaul — Thu, 19 Apr 2012 16:01:21 GMT

If you use var_nm = input(c_num,??8.); it will put a number when it is numeric and . when it is not. Here is an example.

DATA test;

input c_num $;

datalines;

123

12.34
12.34.5

12a4

12)1

23 1

-43

-.5

;

run;

data test1 ;

set test ;

ck_num = input(c_num,??8.) ;

run ;

This gives the following log and proc print; output.

NOTE: There were 8 observations read from the data set WORK.TEST.

NOTE: The data set WORK.TEST1 has 8 observations and 2 variables.

NOTE: DATA statement used (Total process time):

real time 0.01 seconds

cpu time 0.01 seconds

The SAS System 13:59 Monday, April 16, 2012 1

Obs c_num ck_num

1 123 123.00

2 12.34 12.34

3 12.34.5 .

4 12a4 .

5 12)1 .

6 23 23.00

7 -43 -43.00

8 -.5 -0.50

Re: unknown variable name and conversion to numeric

byronk — Thu, 19 Apr 2012 16:37:18 GMT

Exactly and without error messages.

From my understanding of the task, "a) check whether var CNT_&STATE is a character or numeric var", was refering to the variable, not its contents specifically as often times character viarbles only contain numeric data. Also, "b) if it is character var then to change it to numeric", by default, if you change a character field to a numeric, you will lose any non-numeric data as it is nolonger compatible in the new datatype.

On the other hand, if he only wanted to change those from character to numeric where it could without data loss, then you could do another check prior to the sql statemes above to trap the character variables that you didn't want converted.

Re: unknown variable name and conversion to numeric

Ksharp — Fri, 20 Apr 2012 03:09:03 GMT

This example is from documentation. I Just copy it here.

Re: unknown variable name and conversion to numeric

eirhpaul — Fri, 20 Apr 2012 13:31:57 GMT

Right, I skipped the answer to the first part of the question. Fortunately there is a very simple solution.

Use the vtype function to test if CNT_&STATE is charater or numeric.

vtype(cnt_&state); Returns 'N' if it is numeric and 'C' if it is character.