Macro to loop through variables and store results SAS - sas

I have the following variables: A_Bldg B_Bldg C_Bldg D_Bldg. I want to multiply them by INTSF and store the result in a new variable, Sale_i. For example, A_Bldg * INTSF = Sale_A, B_Bldg * INTSF = Sale_B, and so on.
My code is:
%macro loopit(mylist);
%let n=%sysfunc(countw(&mylist));
%do J = 1 %to &n;
%let i = %scan(&mylist,&J);
data test;
set data;
sale_&i. = &i._Bldg * INTSF;
run;
%end;
%mend;
%let list = A B C D;
%loopit(&list);
This only produces Sale_D, which is the last letter in the list. How do I get Sales A-C to appear? The first four lines of code are so I can loop through the text A-D. I thought about doing it with arrays, but didn't know how to choose the variables based on the A-D indicators. Thanks for your help!

You're currently looping through your list and recreating the test dataset every time, so it only appears to have sale_d because you're only viewing the last iteration.
You can clean up your loop by scanning through your list in one data step to solve your problem:
%let list = A B C D;
%macro loopit;
data test;
set data;
%do i = 1 %to %sysfunc(countw(&list.));
%let this_letter = %scan(&list., &i.);
sale_&this_letter. = &this_letter._Bldg * INTSF;
%end;
run;
%mend loopit;
%loopit;

Your %DO loop is in the wrong place. But really you do not need to use macro code to do something that the native SAS code can already do.
data want;
set have ;
array in A_Bldg B_Bldg C_Bldg D_Bldg ;
array out sale_1-sale4 ;
do i=1 to dim(in);
out(i)=intsf*in(i);
end;
run;

Related

Iterate through vector and convert elements to unquoted variable names

The following macro makes an inner join between two tables containing one column from each table in addition to the joining column :
%macro ij(x=,y=,to=".default",xc=,yc=,by=);
%if &to = ".default" %then %let to = &from;
PROC SQL;
CREATE TABLE &to AS
SELECT t1.&xc, t2.&yc, t1.&by
FROM &x t1 INNER JOIN &y t2
ON t1.&by = t2.&by;
RUN;
%mend;
I want to find a way to use several columns in &xc, &yc and &by.
As I don't think I can use vectors of variables.
My idea is to pass parameters as vectors of strings instead of simple variables, for example xc = {"col1" "col2"} and loop through them
using %let some_var= %sysfunc(dequote(&some_string)); to convert them back to variables.
Applied on xc only it would become something like:
%macro ij(x=,y=,to=".default",xc=,yc=,by=);
%if &to = ".default" %then %let to = &from;
PROC SQL;
CREATE TABLE &to AS
SELECT
%do i = 1 %to %NCOL(&xc)
%let xci = %sysfunc(dequote(&xc[1]));
t1.&xci,
%end;
t2.&yc, t1.&by
FROM &x t1 INNER JOIN &y t2
ON t1.&by = t2.&by;
RUN;
%mend;
But this loop fails. How could I make it work ?
Note: this is a simplified example, my ultimate ambition is to build join macros that would be as little verbose as possible and integrate data quality checks.
Really this would be much easier to code use SAS dataset options instead of building complicated macro logic.
proc sql ;
create table want2 as
select *
from sashelp.class(keep=name age)
natural inner join sashelp.class(keep=name height weight)
;
quit;
I would suggest learning how to use data step code instead of SQL code. For most normal data manipulations it is clearer and simpler. Say you wanted to combine IN1 and IN2 on the variable ID and keep the variable A and B from IN1 and the variable X and Y from the IN2.
data out ;
merge in1 in2 ;
by id ;
keep id a b x y ;
run;
Second I would resist the urge to generate too complex a web of macro code. It will make the programs harder to understand for the next programmer. Including yourself two weeks later. Your particular example does not look like something that is worth coding as a macro. You are not really typing less information, just using a few commas in place of where your SQL code would have had keywords like FROM or JOIN.
Now to answer your actual question. To pass in a list of values to macro use a delimited list. When at all possible use space as the delimiter, but especially avoid using comma as the delimiter. This will be easier to type, easier to pass into the macro and easier to use since it matches the SAS language as you can see in the data step above. If you really need to generate code like SQL syntax that uses commas then have the macro code generate them where needed.
%macro ij
(x= /* First dataset name */
,y= /* Second dataset name */
,by= /* BY variable list */
,to= /* Output dataset name. If empty use data step to generate DATAn work name */
,xc= /* Variable list from first dataset */
,yc= /* Variable list from second dataset */
);
%if not %length(&to) %then %do;
* Let SAS generate a name for new dataset ;
data ; run;
%let to=&syslast ;
proc delete data=&to; run;
%end;
%if not %length(&xc) %then %let xc=*;
%if not %length(&yc) %then %let yx=*;
%local i sep ;
proc sql ;
create table &to as
select
%let sep= ;
%do i=1 %to %sysfunc(countw(&by)) ;
&sep.T1.%scan(&by,&i)
%let sep=,;
%end;
%do i=1 %to %sysfunc(countw(&xc)) ;
&sep.T1.%scan(&xc,&i)
%end;
%do i=1 %to %sysfunc(countw(&yc)) ;
&sep.T2.%scan(&yc,&i)
%end;
from &x T1 inner join &y T2 on
%let sep= ;
%do i=1 %to %sysfunc(countw(&by)) ;
&sep.T1.%scan(&by,&i)=T2.%scan(&by,&i)
%let sep=,;
%end;
;
quit;
%mend ij ;
Try it:
options mprint;
%ij(x=sashelp.class,y=sashelp.class,by=name,to=want,xc=age,yc=height weight);
SAS LOG:
MPRINT(IJ): proc sql ;
MPRINT(IJ): create table want as select T1.name ,T1.age ,T2.height ,T2.weight from sashelp.class
T1 inner join sashelp.class T2 on T1.name=T2.name ;
NOTE: Table WORK.WANT created, with 19 rows and 4 columns.
MPRINT(IJ): quit;
Instead of vectors, think simple lists.
Pass your variable lists as unquoted, space separated list of values. The values are SAS variable names that can be scanned out as tokens.
%macro ij (x=, ...);
...
%local i token;
%let i = 1;
%do %while (%length(%scan(&X,&i)));
%let token = %scan(&X,&i);
&token.,/* emit the token as source code */
%let i = %eval(&i+1);
%end;
...
%mend;
%ij ( x = one two three, ... )
Be sure to localize all your macro variables to prevent unwanted side effects outside the macro.
For consistency I try to use i/o related macro parameters that mimic SAS Procs -- data=, out=, file=, ...
Some would say named arguments are verbose!
If your 'proto-code' expects the xci symbol to be some sort of serially numbered variable, it is not. You would have to use %local xc&i; %let xc&i= for assignment, and &&xc&i for resolution. Also, your original code references &from which is not passed.
Building is fun. I would also recommend surveying past conference papers and SAS literature for similar works that may already meet your goal.
You could start with a space-separated list of column names and avoid looping entirely:
/*Define list of columns*/
%let COLS = A B C;
%put COLS = &COLS;
/*Add table alias prefix*/
%let REGEX = %sysfunc(prxparse(s/(\S+)/t1.$1/));
%let COLS = %sysfunc(prxchange(&REGEX,-1,&COLS));
%put COLS = &COLS;
%syscall prxfree(REGEX);
/*Condense multiple spaces to a single space*/
%let COLS = %sysfunc(compbl(&COLS));
%put COLS = &COLS;
/*Replace spaces with commas*/
%let COLS = %sysfunc(translate(&COLS,%str(,),%str( )));
%put COLS = &COLS;
In the end as #Tom noted, SAS dataset options are more convenient, and using them one doesn't need to loop over variables.
Here is the macro I came with :
*--------------------------------------------------------------------------------------------- ;
* JOIN ;
* Performs any join (defaults to inner join). ;
* By default left table is overwritten (convenient for successive left joins) ;
* Performs a natural join so columns should be renamed accordingly through 'rename' parameters ;
*----------------------------------------------------------------------------------------------;
%macro join
(data1= /* left table */
,data2= /* right table */
,keep1= /* columns to keep (default: keep all), don't use with drop */
,keep2=
,drop1= /* columns to drop (default: none), don't use with keep */
,drop2=
,rename1= /* rename statement, such as 'old1 = new1 old2 = new2 */
,rename2=
,j=ij /* join type, either ij lj or rj */
,out= /* created table, by default data1 (left table is overwritten)*/
);
%if not %length(&out) %then %let out = &data1;
%if %length(&keep1) %then %let keep1 = keep=&keep1;
%if %length(&keep2) %then %let keep2 = keep=&keep2;
%if %length(&drop1) %then %let drop1 = drop=&drop1;
%if %length(&drop2) %then %let drop2 = drop=&drop2;
%if %length(&rename1) %then %let rename1 = rename=(&rename1);
%if %length(&rename2) %then %let rename2 = rename=(&rename2);
%let kdr1 =;
%let kdr2 =;
%if (%length(&keep1) | %length(&drop1) | %length(&rename1)) %then %let kdr1 = (&keep1&drop1 &rename1);
%if (%length(&keep2) | %length(&drop2) | %length(&rename2)) %then %let kdr2 = (&keep2&drop2 &rename2);
%if &j=lj %then %let j = LEFT JOIN;
%if &j=ij %then %let j = INNER JOIN;
%if &j=rj %then %let j = RIGHT JOIN;
proc sql;
create table &out as select *
from &data1&kdr1 t1 natural &j &data2&kdr2 t2;
quit;
%mend;
Reproducible Examples:
data temp1;
input letter $ number1 $;
datalines;
a 1
a 2
a 3
b 4
c 8
;
data temp2;
input letter $ letter2 $ number2 $;
datalines;
a c 666
b d 0
;
* left join on common columns into new table temp3;
%join(data1=temp1,data2=temp2,j=lj,out=temp3)
* inner join by default, overwriting temp 1, after renaming to join on another column;
%join(data1=temp1,data2=temp2,drop2=letter,rename2= letter2=letter)

Using max function in macro SAS

I'm trying to find the max of four variables, Value_A Value_B Value_C Value_D, within a macro. I thought I could do %sysfunc(max(value_&i.)) but that isn't working. My full code is:
%let i = (A B C D);
%macro maxvalue;
data want;
set have;
%do j = 1 %to %sysfunc(countw(&list.));
%let i = %scan(&list.,&j.);
value_&i.= Sale_&i. - int_&i.
Max_Value = %sysfunc(max(value_&i.));
%end;
run;
%mend maxvalue;
%maxvalue;
I should specify that I only want the max of the four variables for each observation. Thanks for your help!
Aside from the typo - %let i=(A B C D); should be %let list=(A B C D) - you're a) overcomplicating it, and b) confusing macro syntax with datastep syntax. Whilst you could do this using a macro, there is no need.
Given the variables in question are all prefixed in a similar manner (although it would be even better if they were numerically-suffixed, e.g. Value1, Value2), it's far easier to use arrays and the appropriate functions :
data want ;
set have ;
array sale{*} Sale_A Sale_B Sale_C Sale_D ;
array int{*} Int_A Int_B Int_C Int_D ;
array value{*} Value_A Value_B Value_C Value_D ;
/* Iterate over array */
do i = 1 to dim(sale) ;
value{i} = sum(sale{i},-int{i}) ;
end ;
max_value = max(of value{*}) ;
run ;
As aforementioned, you're over-complicating this, but you can achieve what you're trying to do using macro logic by including another for loop within your max_value assignment. This method involves you taking the max of your four variables and a missing value, which should produce the desired result:
%let list = A B C D;
%macro maxvalue;
data want;
set have;
%do j = 1 %to %sysfunc(countw(&list.));
%let i = %scan(&list.,&j.);
value_&i.= Sale_&i. - int_&i.
%end;
max_value = max(
%do x = 1 %to %sysfunc(countw(&list.));
%let y = %scan(&list.,&x.);
value_&y.,
%end; .
);
run;
%mend maxvalue;
%maxvalue;
Why not just rename your variables to SALE_1 to SALE_4? Then you can reference them with a simple variable list SALE_1-SALE_4.
If you are going to use non-numeric suffixes on lists of similarly named variables then perhaps what you really need is a simple function style macro to generate the lists of variable names based on a base name and list of suffix values.
%macro generate_names(base,list);
&base%sysfunc(tranwrd(%sysfunc(compbl(&list)),%str( ),%str( &base)))
%mend generate_names;
Then it is easier to generate variable lists to use for ARRAY statements
%let suffixes=A B C D;
array sale %generate_names(Sale_,&suffixes);
array int %generate_names(Int_,&suffixes);
array value %generate_names(Value_,&suffixes);
and other statements.
max_value = max(of %generate_names(Value_,&suffixes)) ;

How to force SAS to interpret macro vars as numbers in if condition

SAS is interpreting in_year_tolerance and abs_cost as text vars in the below if statement. Therefore the if statement is testing the alphabetical order of the vars rather than the numerical order. How do I get SAS to treat them as numbers? I have tried sticking the if condition, and the macro vars, in %sysevalf but that made no difference. in_year_tolerance is 10,000,000 and cost can vary, but in the test run starts around 20,000,000 before dropping to 9,000,000 at which point it should exit the loop but doesn't.
%macro set_downward_caps(year, in_year_tolerance, large, small, start, end, increment);
%do c = &start. %to &end. %by &increment.;
%let nominal_down_large_&year. = %sysevalf(&large. + (&c. / 1000));
%let nominal_down_small_&year. = %sysevalf(&small. + (&c. / 100));
%let real_down_large_&year. = %sysevalf((1 - &&nominal_down_large_&year.) * &&rpi&year.);
%let real_down_small_&year. = %sysevalf((1 - &&nominal_down_small_&year.) * &&rpi&year.);
%rates(&year.);
proc means data = output.s_&scenario. noprint nway;
var transbill&year.;
output out = temporary (drop = _type_ _freq_) sum=cost;
run;
data _null_;
set temporary;
call symputx('cost', put(cost,best32.));
run;
data temp;
length scenario $ 30;
scenario = "&scenario.";
large = &&real_down_large_&year.;
small = &&real_down_small_&year.;
cost = &cost.;
run;
data output.summary_of_caps;
set output.summary_of_caps temp;
run;
%let abs_cost = %sysevalf(%sysfunc(abs(&cost)));
%if &in_year_tolerance. > &abs_cost. %then %return;
%end;
%mend set_downward_caps;
Use %sysevalf(&in_year_tolerance > &abs_cost,boolean).
As you have seen, compares are text based. If you put it in an %eval() or %sysevalf() the values will be interpreted as numbers.
The ,boolean option lets it know you want a TRUE/FALSE.

Find three most recent data year for each row

I have a data set with one row for each country and 100 columns (10 variables with 10 data years each).
For each variable I am trying to make a new data set with the three most recent data years for that variable for each country (which might not be successive).
This is what I have so far, but I know its wrong because of the nest loop, and its has same value for recent1 recent2 recent3 however I haven't figured out how to create recent1 recent2 recent3 without two loops.
%macro test();
data Maternal_care_recent;
set wb;
keep country MATERNAL_CARE_2004 -- MATERNAL_CARE_2013 recent_1 recent_2 recent_3;
%let rc = 1;
%do i = 2013 %to 2004 %by -1;
%do rc = 1 %to 3 %by 1;
%if MATERNAL_CARE_&i. ne . %then %do;
recent_&rc. = MATERNAL_CARE_&i.;
%end;
%end;
%end; run; %mend; %test();
You don't need to use a macro to do this - just some arrays:
data Maternal_care_recent;
set wb;
keep country MATERNAL_CARE_2004-MATERNAL_CARE_2013 recent_1 recent_2 recent_3;
array mc {*} MATERNAL_CARE_2004-MATERNAL_CARE_2013;
array recent {*} recent1-recent3;
do i = 2013 to 2004 by -1;
do rc = 1 to 3 by 1;
if mc[i] ne . then do;
recent[rc] = mc[i];
end;
end;
run;
Maybe I don't get your request, but according to your description:
"For each variable I am trying to make a new data set with the three most recent data years for that variable for each country (which might not be successive)" I created this sample dataset with dt1 and dt2 and 2 locations.
The output will be 2 datasets (and generally the number of the variables starting with DT) named DS1 and DS2 with 3 observations for each country, the first one for the first variable, the second one for the second variable.
This is the sample dataset:
data sample_ds;
length city $10 dt1 dt2 8.;
infile datalines dlm=',';
input city $ dt1 dt2;
datalines;
MS,5,0
MS,3,9
MS,3,9
MS,2,0
MS,1,8
MS,1,7
CA,6,1
CA,6,.
CA,6,.
CA,2,8
CA,1,5
CA,0,4
;
This is the sample macro:
%macro help(ds=);
data vars(keep=dt:); set &ds; if _n_ not >0; run;
%let op = %sysfunc(open(vars));
%let nvrs = %sysfunc(attrn(&op,nvars));
%let cl = %sysfunc(close(&op));
%do idx=1 %to &nvrs.;
proc sort data=&ds(keep=city dt&idx.) out=ds&idx.(where=(dt&idx. ne .)) nodupkey; by city DESCENDING dt&idx.; run;
data ds&idx.; set ds&idx.;
retain cnt;
by city DESCENDING dt&idx.;
if first.city then cnt=0; else cnt=cnt+1;
run;
data ds&idx.(drop=cnt); set ds&idx.(where=(cnt<3)); rename dt&idx.=act&idx.; run;
%end;
%mend;
You will run this macro with:
%help(ds=sample_ds);
In the first statement of the macro I select the variables on which I want to iterate:
data vars(keep=dt:); set &ds; if _n_ not >0; run;
Work on this if you want to make this work for your code, or simply rename your variables as DT1 DT2...
Let me know if it is correct for you.
When writing macro code, always keep in mind what has to be done when. SAS processes your code stepwise.
Before your sas code is even compiled, your macro variables are resolved and your macro code is executed
Then the resulting SAS Base code is compiled
Finally the code is executed.
When you write %if MATERNAL_CARE_&i. ne . %then %do, this is macro code interpreded before compilation.
At that time MATERNAL_CARE_&i. is not a variable but a text string containing a macro variable.
The first time you run trhough your %do i = 2013 %to 2004 by -1, it is filled in as MATERNAL_CARE_2013, the second as MATERNAL_CARE_2012., etc.
Then the macro %if statement is interpreted, and as the text string MATERNAL_CARE_1 is not equal to a dot, it is evaluated to FALSE
and recent_&rc. = MATERNAL_CARE_&i. is not included in the code to pass to your compiler.
You can see that if you run your code with option mprint;
The resolution;
options mprint;
%macro test();
data Maternal_care_recent;
set wb;
keep country MATERNAL_CARE_: recent_:;
** The : acts as a wild card here **;
%do i = 2013 %to 2004 %by -1;
if MATERNAL_CARE_&i. ne . then do;
%do rc = 1 %to 3 %by 1;
recent_&rc. = MATERNAL_CARE_&i.;
%end;
end;
%end;
run;
%mend;
%test();
Now, before compilation of if MATERNAL_CARE_&i. ne . then do, only the &i. is evalueated and if MATERNAL_CARE_2013 ne . then do is passed to the compiler.
The compiler will see this as a test if the SAS variable MATERNAL_CARE_1 has value missing, and that is just what you wanted;
Remark:
It is not essential that I moved the if statement above the ``. It is just more efficient because the condition is then evaluated less often.
It is however essential that you close your %ifs and %dos with an %end and your ifs and dos with an end;
Remark:
you do not need %let rc = 1, because %do rc = 1 to 3 already initialises &rc.;
For completeness SAS is compiled stepwise:
The next PROC or data step and its macro code are only considered when the preveous one is executed.
That is why you can write macro variables from a data step or sql select into that will influence the code you compile in your next step,
somehting you can not do for instance with C++ pre compilation;
Thanks everyone. Found a hybrid solution from a few solutions posted.
data sample_ds;
infile datalines dlm=',';
input country $ maternal_2004 maternal_2005
maternal_2006 maternal_2007 maternal_2008 maternal_2009 maternal_2010 maternal_2011 maternal_2012 maternal_2013;
datalines;
MS,5,0,5,0,5,.,5,.,5,.
MW,3,9,5,0,5,0,5,.,5,0
WE,3,9,5,0,5,.,.,.,.,0
HU,2,0,5,.,5,.,5,0,5,0
MI,1,8,5,0,5,0,5,.,5,0
HJ,1,7,5,0,5,0,.,0,.,0
CJ,6,1,5,0,5,0,5,0,5,0
CN,6,1,.,5,0,5,0,5,0,5
CE,6,5,0,5,0,.,0,5,.,8
CT,2,5,0,5,0,5,0,5,0,9
CW,1,5,0,5,0,5,.,.,0,7
CH,0,5,0,5,0,.,0,.,0,5
;
%macro test(var);
data &var._recent;
set sample_ds;
keep country &var._1 &var._2 &var._3;
array mc {*} &var._2004-&var._2013;
array recent {*} &var._1-&var._25;
count=1;
do i = 10 to 1 by -1;
if mc[i] ne . then do;
recent[count] = mc[i];
count=count+1;
end;
end;
run;
%mend;

SAS: Creating lag variables with a do macro

I'm trying to create 4 new lag variables, each one adding an additional lag. The code below produces only the final lag variable, i.e. after running this code there is a new variable called lag_4, but lag_1, lag_2, and lag_3 are not created. Thanks
%macro makelags;
%do i=1 %to 4;
data work.test1;
set work.dataset;
lag_&i = lag&i(id_number);
run;
%end;
%mend makelags;
%makelags;
You need to loop inside the data step, not outside of it.
If you were to loop:
data work.test1;
set work.dataset;
%do i = 1 %to 4;
lag_&i. = lag&i.(id_number);
%end;
run;
(The whole datastep can be inside a macro, or just the %do loop).
The way I'd do it, if I needed a macro (Because, say, the number of lags varies):
%macro lagme(num_lags=);
%do _i = 1 %to &num_lags.;
lag_&_i. = lag&_i.(id_number);
%end;
%mend lagme;
data mydata;
set olddata;
%lagme(num_lags=4);
run;
Your code is overwriting dataset test1 4 times keeping only the version created by the last %do iteration.
Try moving the %do cycle inside the data step:
data work.test1;
set work.dataset;
%do i=1 %to 4;
lag_&i = lag&i(id_number);
%end;
run;