Polynomials in character form to numeric (SAS) - sas

I have a SAS dataset which contains one column of polynomials. For example, X1**(-2)+X1**(2).
Is there a function to transform this into a numeric expression?
Many thanks,

If I understand you correctly, I don't think there is a specific function that will easily let you do this. You have two options - write your own logic to interpret the polynomial expressions, or use call execute to have SAS write out a (potentially very long) data step for you, assuming that the polynomials are all entered as valid data step code. Here's a call execute approach:
data have;
input x1 polynomial $255.;
infile datalines truncover;
datalines;
1 X1**(-2)+X1**(2)
2 X1**(-1)+X1**(1)
3 X1**(1)+X1**(-1)
;
run;
data _null_;
set have end = eof;
if _n_ = 1 then call execute('data want; set have; select(_n_);');
call execute(catx(' ','when(',_N_,') y =',polynomial,';'));
if eof then call execute('end; run;');
run;

Convert them to macro variables, and then resolve them into a calculation...
Using the dataset example in user667489's answer :
/* Create numbered macro variables, 1 per row of data */
data _null_ ;
set have end=eof ;
call symputx(cats('POLY',_n_),polynomial) ;
if eof then call symputx('POLYN',_n_) ;
run ;
%MACRO ROWLOOPER ;
%DO N = 1 %TO &POLYN ;
if _n_ = &N then result = &&POLY&N ;
%END ;
%MEND ;
data want ;
set have ;
/* Not very efficient, looping over all polynomials on each row of data */
/* So for 3 rows, you'll perform 9 iterations here */
%ROWLOOPER ;
run ;
Or, alternatively, write your dataset out into a SAS program, and %inc that program :
data _null_ ;
file "polynomials.sas" ;
set have end=eof ;
if _n_ = 1 then do ;
put "data poly;" ;
put " set have;" ;
end ;
put " result = " polynomial ";" ;
if eof then put "run;" ;
run ;
%inc "polynomials.sas" ;

Related

sas macro : how to make multiful column using macro?

I'm SAS user.
I want to assign year columns using date values.
for example, here is my code, below.
I want to make Y_2010, Y_2011, Y_2012 , Y_2013, Y_2014 in work.total data set.
but there is only Y_2014 as a result.
How can I change the code as I can get right result which I intended first?
options mcompilenote = all;
%let a = Y_ ;
%macro B(YMIN, YMAX) ;
%do i = &YMIN %to &YMAX ;
DATA TOTAL ;
SET SASUSER.EMPDATA ;
IF YEAR(HIREDATE) = &i THEN &a&i = 1 ;
ELSE &a&i = 0 ;
RUN;
%end;
%mend;
%B (2010, 2014) ;
Because you are repeatedly re-creating the output dataset only the final version is available. To fix the macro move the %DO loop inside the DATA step so that you are generating all of the variables in a single data step.
%macro B(YMIN, YMAX) ;
DATA TOTAL ;
SET SASUSER.EMPDATA ;
%do i = &YMIN %to &YMAX ;
IF YEAR(HIREDATE) = &i THEN &a&i = 1 ;
ELSE &a&i = 0 ;
%end;
RUN;
%mend;
But there is no need to a macro for this. Just use normal SAS statements. For example you could use an ARRAY statement to define the variables and then loop over the array and set the values. Note that the result of a boolean expression in SAS is 0 when false and 1 when true so you can eliminate the IF/THEN/ELSE statement and just use an assignment statement.
DATA TOTAL ;
SET SASUSER.EMPDATA ;
array &a &a&ymin - &a&ymax;
do i=&ymin to &ymax ;
&a[i-&ymin+1] = (year(hiredata)=i);
end;
drop i;
RUN;

Do loop for creating new variables in SAS

I am trying to run this code
data swati;
input facility_id$ loan_desc : $50. sys_name :$50.;
cards;
fac_001 term_loan RM_platform
fac_001 business_loan IQ_platform
fac_002 business_loan BUSES_termloan
fac_002 business_loan RM_platform
fac_003 overdrafts RM_platform
fac_003 RCF IQ_platform
fac_003 term_loan BUSES_termloan
;
proc contents data=swati out=contents(keep=name varnum);
run;
proc sort data=contents;
by varnum;
run;
data contents;
set contents ;
where varnum in (2,3);
run;
data contents;
set contents;
summary=catx('_',name, 'summ');
run;
data _null_;
set contents;
call symput ("name" || put(_n_ , 10. -L), name);
call symput ("summ" || put (_n_ , 10. -L), summary);
run;
options mlogic symbolgen mprint;
%macro swati;
%do i = 1 %to 2;
proc sort data=swati;
by facility_id &&name&i.;
run;
data swati1;
set swati;
by facility_id &&name&i.;
length &&summ&i. $50.;
retain &&summ&i.;
if first.facility_id then do;
&&summ&i.="";
end;
if first.&&name&i. = last.&&name&i. then &&summ&i.=catx(',',&&name&i., &&summ&i.);
else if first.&&name&i. ne last.&&name&i. then &&summ&i.=&&name&i.;
run;
if last.facility_id ;
%end;
%mend;
%swati;
This code will create two new variables loan_desc_summ and sys_name_summ which has values of the all the loans_desc in one line and the sys_names in one line seprated by comma example (term_loan, business_loan), (RM_platform, IQ_platform) But if a customer has only one loan_desc the loan_summ should only have its value twice.
The problem while running the do loop is that after running this code, I am getting the dataset with only the sys_name_summ and not the loan_desc_summ. I want the dataset with all the five variables facility_id, loan_desc, sys_name, loan_desc_summ, sys_name_summ.
Could you please help me in finding out if there is a problem in the do loop??
Your loop is always starting with the same input dataset (swati) and generating a new dataset (SWATI1). So only the last time through the loop has any effect. Each loop would need to start with the output of the previous run.
You also need to fix your logic for eliminating the duplicates.
For example you could change the macro to:
%macro swati;
data swati1;
set swati;
run;
%do i = 1 %to 2;
proc sort data=swati1;
by facility_id &&name&i.;
run;
data swati1;
set swati1;
by facility_id &&name&i ;
length &&summ&i $500 ;
if first.facility_id then &&summ&i = ' ' ;
if first.&&name&i then catx(',',&&summ&i,&&name&i);
if last.facility_id ;
run;
%end;
%mend;
Also your program could be a lot smaller if you just used arrays.
data want ;
set have ;
by facility_id ;
array one loan_desc sys_name ;
array two $500 loan_desc_summ sys_name_summ ;
retain loan_desc_summ sys_name_summ ;
do i=1 to dim(one);
if first.facility_id then two(i)=one(i) ;
else if not findw(two(i),one(i),',','t') then two(i)=catx(',',two(i),one(i));
end;
if last.facility_id;
drop i loan_desc sys_name ;
run;
If you want to make it more flexible you can put the list of variable names into a macro variable.
%let varlist=loan_desc sys_name;
You could then generate the list of new names easily.
%let varlist2=%sysfunc(tranwrd(&varlist,%str( ),_summ%str( )))_summ ;
Then you can use the macro variables in the ARRAY, RETAIN and DROP statements.

Increment variable name

Is it possible to increment different prefixed variable names in a simple way? For example, if my dataset has columns for Score1 all the way to Score20, I can simply do:
input Score1-Score20;
But what if I have Score1 Rank1 Total1 to Score20 Rank20 Total20, is there a way to increment these without manually typing out each one? So the result would look like:
Score1 Rank1 Total1 Score2 Rank2 Total2 Score3 Rank3 Total3 etc...
Do you care if the variables are created in a different order than in the input file? If not then use an ARRAY. Try this example.
data x ;
array x(3,20) a1-a20 b1-b20 c1-c20 ;
infile cards truncover;
do block=1 to 20;
do item=1 to 3;
input x(item,block) #;
end;
end;
put (_all_) (=);
list;
cards;
1 1 1 2 2 2 3 3 3 4 4 4 5 5 5
;
If you need them in that order then you need to use some type of code generation.
You could create a simple function style macro to emit the list of names.
%macro namelist(baselist,n);
%local i j;
%do i=1 %to &n ;
%do j=1 %to %sysfunc(countw(&baselist));
%scan(&baselist,&j)&i
%end;
%end;
%mend namelist;
...
input %namelist(Rank Total Score,20) ;
Or you could use a simple data step to build the list into a macro variable.
data _null_;
length i 8 basename $30 namelist $32000;
do i=1 to 20 ;
do basename='Rank ','Total','Score';
namelist=catx(' ',namelist,cats(basename,i));
end;
end;
call symputx('namelist',namelist);
run;
...
input &namelist ;
You could probably do a macro for this. I think this would work:
%macro mymacro(runs);
%do i=1 %to &runs;
input Score&i Rank&i Total&i;
run;
%end;
%mend create;
%mymacro(20)
Try here for better documentation: https://support.sas.com/documentation/cdl/en/mcrolref/61885/HTML/default/viewer.htm#a000543755.htm
The same question was asked here earlier in the week, the answer is the same.
https://communities.sas.com/t5/General-SAS-Programming/Variables-listing/m-p/238350#M34601
You could create a macro to create the names.
data _null_;
length var $1000.;
do i=1 to 10;
var=catt(var, " Total"||put(i, 2. -l), " Male"||put(i, 2. -l), " Female"||put(i, 2. -l));
end;
call symputx('input_list', var);
run;
%put &input_list;

Create Program Code out of excel table in SAS

For a Macro, I want to create an automated ATTRIB Statement.
I have an exel Table with all variable names, formats, lables and lengths.
Now I want SAS to read each row and pass it into:
%LET Format_VARIABLE = FORMAT = &For LENGTH = &len LABEL = "&lab";
Any ideas how to archive this?
Assuming you have a dataset (called metadata) containing all of you variable names (vname), formats (vfmt), lengths (vlen) and labels (vlbl) from Excel :
/* Create VNAME1-VNAMEx, VFMT1-VFMTx etc */
data _null_ ;
set metadata end=eof ;
call symputx(cats('VNAME',_n_),vname) ;
call symputx(cats('VFMT',_n_),vfmt) ;
call symputx(cats('VLEN',_n_),vlen) ;
call symputx(cats('VLBL',_n_),vlbl) ;
if eof then call symputx('VNUM',_n_) ;
run ;
%MACRO BUILD_ATTRIB ;
/* Iterate over each set of macro variables and resolve into `attrib` statement */
attrib %DO I = 1 %TO &VNUM ;
&&VNAME&I format=&&VFMT&I length=&&VLEN&I label="&&VLBL&I"
%END ;
;
%MEND ;
/* To use in a datastep */
data want ;
%BUILD_ATTRIB ;
set have ;
run ;

How can I use %SCAN within a macro variable name?

I'm trying to write robust code to assign values to macro variables. I want the names of the macro variables to depend on values coming from the variable 'subgroup'. So subgroup could equal 1, 2, or 45 etc. and thus have macro variable names trta_1, trta_2, trt_45 etc.
Where I am having difficulty is calling the macro variable name. So instead of calling e.g. &trta_1 I want to call &trta_%SCAN(&subgroups, &k), which resolves to trta_1 on the first iteration. I've used a %SCAN function in the macro variable name, which is throwing up a warning 'WARNING: Apparent symbolic reference TRTA_ not resolved.'. However, the macro variables have been created with values assigned.
How can I resolve the warning? Is there a function I could run with the %SCAN function to get this to work?
data data1 ;
input subgroup trta trtb ;
datalines ;
1 30 58
2 120 450
3 670 3
run;
%LET subgroups = 1 2 3 ;
%PUT &subgroups;
%MACRO test;
%DO k=1 %TO 3;
DATA test_&k;
SET data1;
WHERE subgroup = %SCAN(&subgroups, &k);
CALL SYMPUTX("TRTA_%SCAN(&subgroups, &k)", trta, 'G');
CALL SYMPUTX("TRTB_%SCAN(&subgroups, &k)", trtb, 'G');
RUN;
%PUT "&TRTA_%SCAN(&subgroups, &k)" "&TRTB_%SCAN(&subgroups, &k)";
%END;
%MEND test;
%test;
Using the structure you've provided the following will achieve the result you're looking for.
data data1;
input subgroup trta trtb;
datalines;
1 30 58
2 120 450
3 670 3
;
run;
%LET SUBGROUPS = 1 2 3;
%PUT &SUBGROUPS;
%MACRO TEST;
%DO K=1 %TO 3;
%LET X = %SCAN(&SUBGROUPS, &K) ;
data test_&k;
set data1;
where subgroup = &X ;
call symputx(cats("TRTA_",&X), trta, 'g');
call symputx(cats("TRTB_",&X), trtb, 'g');
run;
%PUT "&&TRTA_&X" "&&TRTB_&X";
%END;
%MEND TEST;
%TEST;
However, I'm not sure this approach is particularly robust. If your list of subgroups changes you'd need to change the 'K' loop manually, you can determine the upper bound of the loop by dynamically counting the 'elements' in your subgroup list.
If you want to call the macro variables you've created later in your code, you could a similar method.
data data2;
input subgroup value;
datalines;
1 20
2 25
3 15
45 30
;
run ;
%MACRO TEST2;
%DO K=1 %TO 3;
%LET X = %SCAN(&SUBGROUPS, &K) ;
data data2 ;
set data2 ;
if subgroup = &X then percent = value/&&TRTB_&X ;
format percent percent9.2 ;
run ;
%END;
%MEND TEST2;
%TEST2 ;
Effectively, you're re-writing data2 on each iteration of the loop.
This should cover your requirements. You can load and unload an array of macro variable without a macro. I have included an alternate method of unloading a macro variable array with a macro for comparison.
Load values into macro variables including Subgroup number within macro variable name e.g. TRTA_45.
data data1;
input subgroup trta trtb;
call symput ('TRTA_'||compress (subgroup), trta);
call symput ('TRTB_'||compress (subgroup), trtb);
datalines;
1 30 58
2 120 450
3 670 3
45 999 111
;
run;
No need for macro to load or refer to macro variables.
%put TRTA_45: &TRTA_45.;
%let Subgroup_num = 45;
%put TRTB__&subgroup_num.: &&TRTB_&subgroup_num.;
If you need to loop through the macro variables then you can use Proc SQL to generate a list of subgroups.
proc sql noprint;
select subgroup
, count (*)
into :subgroups separated by ' '
, :No_Subgroups
from data1
;
quit;
%put Subgroups: &subgroups.;
%put No_Subgroups: &No_Subgroups.;
Use a macro to loop through the macro variable array and populate a table.
%macro subgroups;
data subgroup_data_macro;
%do i = 1 %to &no_subgroups.;
%PUT TRTA_%SCAN(&subgroups, &i ): %cmpres(&TRTA_%SCAN(&subgroups, &i ));
%PUT TRTB_%SCAN(&subgroups, &i ): %cmpres(&TRTB_%SCAN(&subgroups, &i ));
subgroup = %SCAN(&subgroups, &i );
TRTA = %cmpres(&TRTA_%SCAN(&subgroups, &i ));
TRTB = %cmpres(&TRTB_%SCAN(&subgroups, &i ));
output;
%end;
run;
%mend subgroups;
%subgroups;
Or use a data step (outside a macro) to loop through the macro variable array and populate a table.
data subgroup_data_sans_macro;
do i = 1 to &no_subgroups.;
subgroup = SCAN("&subgroups", i );
TRTA = input (symget (compress ('TRTA_'||subgroup)),20.);
TRTB = input (symget (compress ('TRTB_'||subgroup)),20.);
output;
end;
run;
Ensure both methods (within and without a macro) produce the same result.
proc compare
base = subgroup_data_sans_macro
compare = subgroup_data_macro
;
run;