SAS store macro reference in macro variable - sas

I want to store a list of macro references in another macro variable and then change the content of one of the referenced variables.
As example:
%LET String=FirstString;
%LET KeepMacroNotString=&String;
%PUT &String = &KeepMacroNotString ?;
%LET String=String changed;
%PUT &String = &KeepMacroNotString?;
In the end I would like that %PUT &KeepMacroNotString resolves to "String changed". However it sticks to the first assignment.
Any ideas?
Thx, Lubenja

Much easier to do with a data step.
data _null_;
call symputx('KeepMacroNotString','&String');
run;

I found the solution:
A combination of the %NRSTR function and the %UNQUOTE function do the trick:
%LET String=FirstString;
%LET KeepMacroNotString=%NRSTR(&String);
%PUT &String = &KeepMacroNotString ?;
%LET String=String changed;
%PUT &String = %UNQUOTE(&KeepMacroNotString)?;
Explanation: First you have to mask the "&" to prevent the macro from being resolved (%NRSTR()).
But when you want to use the marco, then you have to unquote it again (%UNQUOTE()).

I wouldn't use this approach, but if you don't mind warning messages in the log (I do), you could in theory just change the order of your statements:
WARNING: Apparent symbolic reference STRING not resolved.
57
58 %LET KeepMacroNotString=&String;
59
60 %LET String=FirstString;
61 %PUT &String = &KeepMacroNotString ?;
FirstString = FirstString ?
62
63 %LET String=String changed;
64 %PUT &String = &KeepMacroNotString?;
String changed = String changed?
This is basically an ugly way of accomplishing the same sort of indirection that Tom did more gracefully. Key point being that that the macro variable KeepMacroNotString is given a value of &String, not the resolved value.
In a macro setting, this can also be accomplished by assigning default value as a macro variable reference, e.g.:
59 %macro indirect(String=
60 ,KeepMacroNotString=&string
61 );
62 %put _local_;
63 %put &string = &keepmacronotstring;
64 %mend indirect;
65 %indirect(string=Hi)
INDIRECT KEEPMACRONOTSTRING &string
INDIRECT STRING Hi
Hi = Hi

Related

put values to a file using functions without creating new variables

I am processing a dataset, the contents of which I do not know in advance. My target SAS instance is 9.3, and I cannot use SQL as that has certain 'reserved' names (such as "user") that cannot be used as column names.
The puzzle looks like this:
data _null_;
set some.dataset; file somefile;
/* no problem can even apply formats */
put name age;
/* how to do this without making new vars? */
put somefunc(name) max(age);
run;
I can't put var1=somefunc(name); put var1; as that may clash with a source variable named var1.
I'm guessing the answer is to make some macro function that will read the dataset header and return me a "safe" (non-clashing) variable, or an fcmp function in a format, but I thought I'd check with the community to see - is there some "old school" way to outPUT directly from a function, in a data step?
Temporary array?
34 data _null_;
35 set sashelp.class;
36 array _n[*] _numeric_;
37 array _f[3] _temporary_;
38 put _n_ #;
39 do _n_ = 1 to dim(_f);
40 _f[_n_] = log(_n[_n_]);
41 put _f[_n_]= #;
42 end;
43 put ;
44 run;
1 _f[1]=2.6390573296 _f[2]=4.2341065046 _f[3]=4.7229532216
2 _f[1]=2.5649493575 _f[2]=4.0342406382 _f[3]=4.4308167988
3 _f[1]=2.5649493575 _f[2]=4.1789920363 _f[3]=4.5849674787
4 _f[1]=2.6390573296 _f[2]=4.1399550735 _f[3]=4.6298627986
5 _f[1]=2.6390573296 _f[2]=4.1510399059 _f[3]=4.6298627986
6 _f[1]=2.4849066498 _f[2]=4.0483006237 _f[3]=4.4188406078
7 _f[1]=2.4849066498 _f[2]=4.091005661 _f[3]=4.4367515344
8 _f[1]=2.7080502011 _f[2]=4.1351665567 _f[3]=4.7229532216
9 _f[1]=2.5649493575 _f[2]=4.1351665567 _f[3]=4.4308167988
The PUT statement does not accept a function invocation as a valid item for output.
A DATA step does not do columnar functions as you indicated with max(age) (so it would be even less likely to use such a function in PUT ;-)
Avoid name collisions
My recommendation is to use a variable name that is highly unlikely to collide.
_temp_001 = somefunc(<var>);
_temp_002 = somefunc2(<var2>);
put _temp_001 _temp_002;
drop _temp_:;
or
%let tempvar = _%sysfunc(rand(uniform, 1e15),z15.);
&tempvar = somefunc(<var>);
put &tempvar;
drop &tempvar;
%symdel tempvar;
Repurpose
You can re-purpose any automatic variable that is not important to the running step. Some omni-present candidates include:
numeric variables:
_n_
_iorc_
_threadid_
_nthreads_
first.<any-name> (only tweak after first. logic associated with BY statement)
last.<any-name>
character variables:
_infile_ (requires an empty datalines;)
_hostname_
avoid
_file_
_error_
I think you would be pretty safe choosing some unlikely to collide names. An easy way to generate these and still make the code somewhat readable would be to just hash a string to create a valid SAS varname and use a macro reference to make the code readable. Something like this:
%macro get_low_collision_varname(iSeed=);
%local try cnt result;
%let cnt = 0;
%let result = ;
%do %while ("&result" eq "");
%let try = %sysfunc(md5(&iSeed&cnt),hex32.);
%if %sysfunc(anyalpha(%substr(&try,1,1))) gt 0 %then %do;
%let result = &try;
%end;
%let cnt = %eval(&cnt + 1);
%end;
&result
%mend;
The above code takes a seed string and just adds a number to the end of it. It iterates the number until it gets a valid SAS varname as output from the md5() function. You could even then test the target dataset name to make sure the variable doesn't already exist. If it does build that logic into the above function.
Test it:
%let my_var = %get_low_collision_varname(iSeed=this shouldnt collide);
%put &my_var;
data _null_;
set sashelp.class;
&my_var = 1;
put _all_;
run;
Results:
Name=Alfred Sex=M Age=14 Height=69 Weight=112.5 C34FD80ED9E856160E59FCEBF37F00D2=1 _ERROR_=0 _N_=1
Name=Alice Sex=F Age=13 Height=56.5 Weight=84 C34FD80ED9E856160E59FCEBF37F00D2=1 _ERROR_=0 _N_=2
This doesn't specifically answer the question of how to achieve it without creating new varnames, but it does give a practical workaround.

passing date variable to macro for sysfunc processing

below is my little problem to create a macro and passing in a date variable. Without using the date variable, it works with results as below.
%macro x();
%let i=-1;
%let dts = %sysfunc(today());
%put &dts; /*ok*/
%let yymm1 = %sysfunc(intnx(MONTH,&dts,&i));
%put &yymm1; /*ok*/
%let mth_beg = %sysfunc(intnx(MONTH,&dts,&i,B),date9.);
%let mth_end = %sysfunc(intnx(MONTH,&dts,&i,E),date9.);
%put &mth_beg &mth_end; /*01JAN2018 31JAN2018*/
/*** proc sql code below ** */
%mend;
%x();
log:
21231
21185
01JAN2018
31JAN2018
Now I create a macro around it and got the following error:
%macro x(dts1);
%let i=-1;
/*%let dts = %sysfunc(today());*/
%let dts = %sysfunc(&dts1);
%put &dts; /*ok*/
%let yymm1 = %sysfunc(intnx(MONTH,&dts,&i));
%put &yymm1; /*ok*/
%let mth_beg = %sysfunc(intnx(MONTH,&dts,&i,B),date9.);
%let mth_end = %sysfunc(intnx(MONTH,&dts,&i,E),date9.);
%put &mth_beg &mth_end; /*01JAN2018 31JAN2018*/
/*** proc sql code below ** */
%mend;
%x(16JAN2018);
ERROR: Function name missing in %SYSFUNC or %QSYSFUNC macro function reference.
JAN2018)
ERROR: Expected close parenthesis after macro function invocation not found.
))
ERROR: Expected close parenthesis after macro function invocation not found.
ERROR: Expected close parenthesis after macro function invocation not found.
,B),date9.) ,E),date9.)
I am not sure how to let SAS treat the date passed in as a recognized date. I know i probably used the sysfunc(&dts) wrongly or the date passed in need to adhere to certain format. i just want the date to replace today(). Can you help? I am a SAS newbie.
thanks
Wrap the date in " and end with a d. That will tell SAS to convert the string to a date:
%macro x(dts1);
%let i=-1;
/*%let dts = %sysfunc(today());*/
%let dts = "&dts1"d; /*Change here!*/
%put &dts; /*ok*/
%let yymm1 = %sysfunc(intnx(MONTH,&dts,&i));
%put &yymm1; /*ok*/
%let mth_beg = %sysfunc(intnx(MONTH,&dts,&i,B),date9.);
%let mth_end = %sysfunc(intnx(MONTH,&dts,&i,E),date9.);
%put &mth_beg &mth_end; /*01JAN2018 31JAN2018*/
/*** proc sql code below ** */
%mend;
%x(16JAN2018);
change %let dts = %sysfunc(&dts1); to
%let dts = %sysfunc(inputn(&dts1,date9. ));
SAS stores dates as the number of days since 01JAN1960. So if you do not attach a date format to the date value it will just look like an integer.
%let today=%sysfunc(today());
You can then use that integer anywhere you would use a date value.
%let next_month=%sysfunc(intnx(month,&today,1,b));
You can also represent dates by using a date literal. To make a date literal you represent the date value using something the DATE informat can read (like 16FEB2018, 16feb18, 16-FEB-2018, etc.) enclosed in quotes with the letter d appended.
%let today="%sysfunc(today(),date9)"d ;
%let date_string=13FEB2018;
%let date_value="&date_string"d ;
So date literals will work in SAS code and when you use the %sysfunc() macro function to call a SAS function (like INTNX) and they will work in the %sysevalf() macro function. But the %eval() macro function will not recognize date literals. So you will need to use %sysevalf() if you want use arithmetic or comparisons of date literals in macro logic.
%if %sysevalf(&today > '01JAN2018'd) %then ....
%let tomorrow=%sysevalf(&today +1);

Inconsistent Macro Variable Data Type

I'm trying to make a simple macro that checks whether a specific macro variable is either missing or does not exist. Normally, this would require two statements: a %symexist, and if it does exist, additional logic to detect whether it's a null value. The below code combines all of that into one.
%macro isnull(macvar);
%sysevalf(%superq(%superq(macvar)) NE %str(), boolean);
%mend isnull;
Problem
I cannot use %isNull() in a %if statement, because the returned value always seems to be a character. This behavior differs if it's in open code or within a macro itself.
What I've tried
I've narrowed it down to the macro not resolving as a numeric value. I've tried everything from enclosing it with %sysfunc(putn()) to %cmpres() to %sysfunc(compress()). If it's in open code, it is numeric. If it's in another macro, it's character. You can see it with this code:
/* Miss2 resolves incorrectly as character */
%macro check;
%let miss1=%sysevalf(%superq(asdf) =, boolean);
%let miss2=%isNull(asdf);
%put Miss1: %datatyp(&miss1);
%put Miss2: %datatyp(&miss2);
%mend;
%check;
/* Miss2 resolves correctly as numeric */
%let miss1=%sysevalf(%superq(asdf) =, boolean);
%let miss2=%isNull(asdf);
%put Miss1: %datatyp(&miss1);
%put Miss2: %datatyp(&miss2);
Want
I want to be able to use this in a %if statement to check whether a macro both exists and is not blank simultaneously.
%macro foo;
%if(%isNull(sysuserid) = 1) %then %put sysuserid exists;
%if(%isNull(asdffdsa) = 0) %then %put asdffdsa does not exist;
%if(%isNull(sysuserid) > 0) %then %put this should resolve;
%if(%isNull(asdffdsa) > 0) %then %put this should not resolve;
%mend;
%foo;
The problem you have here is that your macro has a semicolon in it. See this:
174 %macro check;
175 %let miss1=%sysevalf(%superq(asdf) NE %str(), boolean);
176 %let miss2=%missm(asdf);
177
178 %put &miss1. Miss1: %datatyp(&miss1);
179 %put &miss2. Miss2: %datatyp(%unquote(&miss2));
180 %mend;
181 %check;
WARNING: Apparent symbolic reference ASDF not resolved.
WARNING: Apparent symbolic reference ASDF not resolved.
0 Miss1: NUMERIC
0; Miss2: CHAR
Note the ;? Compile this instead:
%macro missm(macvar);
%sysevalf(%superq(%superq(macvar)) NE %str(), boolean)
%mend missm;
and you get:
185 %macro check;
186 %let miss1=%sysevalf(%superq(asdf) NE %str(), boolean);
187 %let miss2=%missm(asdf);
188
189 %put &miss1. Miss1: %datatyp(&miss1);
190 %put &miss2. Miss2: %datatyp(%unquote(&miss2));
191 %mend;
192 %check;
WARNING: Apparent symbolic reference ASDF not resolved.
WARNING: Apparent symbolic reference ASDF not resolved.
0 Miss1: NUMERIC
0 Miss2: NUMERIC
I'll also add that I think you should not skip the %symexist. You get a warning in the log the way you're doing it here, that's easily avoided.
%macro missm(macvar);
%if %symexist(&macvar.) %then
%sysevalf(%superq(%superq(macvar)) NE , boolean)
%else
0
%mend missm;
You'll also note I remove your unnecessary %str() which doesn't really do anything. See Chang Chung's seminal paper, Is This Macro Parameter Blank, for why (and for some more great information, if you haven't already read it).
Finally - I think I would suggest renaming your macro and/or reversing the direction. %if %missm says to me 'if this macro variable is missing', which is the opposite of what you're telling: TRUE is returned if it is NOT missing. %missm should return true for EQ [blank], or NOT %symexist; it should return false for [defined and contains a value].

How to prevent CATx functions from evaluating expression

When calling CATT() function with %sysfunc, is there a way to stop it from evaluating an expression?
For example given the code:
%let date=10-13-2015;
%put %sysfunc(catt(The date Is:,&date));
I would like it to return:
The date Is:10-13-2015
Because 10-13-2015 is just a text string. But instead CATT() sees hyphen as a subtraction sign and evaluates it as a numeric expression, returning:
The date Is:-2018
I have tried macro quoting, but doesn't change anything, I suppose because I need to somehow hide the values from CATT(). Seems if any argument to CATT looks like an expression, it will be treated as such.
Another example:
%let value=2 and 3;
%put %sysfunc(catt(The value Is:,&value));
The value Is:1
Provided you can do so, just remove the comma - there's no need to separate it into an individual parameter (unless you're using catx() rather than catt():
%let date=10-13-2015;
%put %sysfunc(catt(The date Is: &date));
Personally, I think the best way to work is to store the date as a SAS date value and then use the second (optional) parameter of %sysfunc to apply the formatting. This provides better flexibility.
%let date = %sysfunc(mdy(10,13,2015));
%put The date Is: %sysfunc(sum(&date),mmddyyd10.);
If you are insistent on the original approach and are using catx(), then I don't know how to do it exactly. The closest I could get was to insert a piece of text so it couldn't be interpreted as an expression, and then remove that text afterwards using tranwrd. Pretty, ugly, and it leaves a space:
%let date=10-13-2015;
%let tmp=%sysfunc(catx(#, The date Is: , UNIQUE_STRING_TO_REMOVE&date ));
%let want=%sysfunc(tranwrd(&tmp, UNIQUE_STRING_TO_REMOVE, ));
%put &want;
Gives:
The date Is:# 10-13-2015
I also tried every combination of macro quoting, and scanned through the entire SAS function list and couldn't see any other viable options.
I don't see an easy way around this, unfortunately. I do see that you could in theory pass this through an FCMP function, though since FCMP doesn't allow true variable arguments, that isn't ideal either, but...
proc fcmp outlib=work.funcs.funcs;
function catme(delim $, in_string $) $;
length _result $1024;
length _new_delim $1;
_new_delim = scan(in_string,1,delim);
do _i = 1 to countc(in_string,delim);
_result = catx(_new_delim, _result, scan(in_string,_i+1,delim));
end;
return(_result);
endfunc;
quit;
options cmplib=work.funcs;
%let date=10-13-2015;
%put %sysfunc(catme(|,:|The date Is| &date.));
Or add quotes to the argument and then remove them after the CATx.
%sysfunc(dequote(%sysfunc(catt(.... ,"&date."))))
All messy.
The problem with %SYSFUNC() evaluating the arguments is not limited to the CAT() series of functions. Any function that accepts numeric values will result in SAS attempting to evaluate the expression provided.
This can be a useful feature. For example:
%let start_dt=10OCT2012 ;
%put %sysfunc(putn("&start_dt"d +1,date9));
You don't need to use CAT() functions to work with macro variables. Just expand the values next to each other and the are "concatenated".
%let date=10-13-2015;
%put The date Is:&date;
If you want to make a macro that works like the CATX() function then that is also not hard to do.
%macro catx /parmbuff ;
%local dlm return i ;
%if %length(&syspbuff) > 2 %then %do;
%let syspbuff = %qsubstr(&syspbuff,2,%length(&syspbuff)-2);
%let dlm=%qscan(&syspbuff,1,%str(,),q);
%let return=%qscan(&syspbuff,2,%str(,),q);
%do i=3 %to %sysfunc(countw(&syspbuff,%str(,),q));
%let return=&return.&dlm.%qscan(&syspbuff,&i,%str(,),q);
%end;
%end;
&return.
%mend catx;
%put %catx(|,a,b,c);
a|b|c
%put "%catx(",",a,b,c,d)";
"a","b","c","d"
Slightly less insane function-style macro without the dosubl:
%macro catx() /parmbuff;
%local rc dlm i params OUTSTR QWORD outstr;
%let SYSPBUFF = %qsubstr(&SYSPBUFF,2,%length(&SYSPBUFF)-2);
%let dlm = %qscan(&SYSPBUFF,1,%str(,));
%let params = %qsubstr(&SYSPBUFF,%index(&SYSPBUFF,%str(,))+1);
%let i = 1;
%let QWORD = %scan(&PARAMS,&i,%str(,));
%let OUTSTR = &QWORD;
%do %while(&QWORD ne);
%let i = %eval(&i + 1);
%let QWORD = %scan(&PARAMS,&i,%str(,));
%if &QWORD ne %then %let OUTSTR = &OUTSTR.&DLM.&QWORD;
%end;
%unquote(&OUTSTR)
%mend catx;
%put %catx(%str( ),abc,10 - 1 + 2,def);
Somewhat more insane but apparently working option - use %sysfunc(dosubl(...)) and lots of macro logic to create a function-style macro that takes input in the same way as %sysfunc(catx(...)), but forces catx to treat all input as text by quoting it and calling it in a data step.
%macro catxt() /parmbuff;
%local rc dlm i params QPARAMS QWORD outstr;
%let SYSPBUFF = %qsubstr(&SYSPBUFF,2,%length(&SYSPBUFF)-2);
%let dlm = %qscan(&SYSPBUFF,1,%str(,));
%let params = %qsubstr(&SYSPBUFF,%index(&SYSPBUFF,%str(,))+1);
%let i = 1;
%let QWORD = "%scan(&PARAMS,&i,%str(,))";
%let QPARAMS = &QWORD;
%do %while(&QWORD ne "");
%let i = %eval(&i + 1);
%let QWORD = "%scan(&PARAMS,&i,%str(,))";
%if &QWORD ne "" %then %let QPARAMS = &QPARAMS,&QWORD;
%end;
%let rc = %sysfunc(dosubl(%str(
data _null_;
call symput("OUTSTR",catx("&dlm",%unquote(&QPARAMS)));
run;
)));
&OUTSTR
%mend catxt;
%put %catxt(%str( ),abc,10 - 1 + 2,def);
Although this uses a data step to execute catx, dosubl allows the whole thing to be run in any place where you could normally use %sysfunc(catx(...)).

How do I work out the data type of my macro variable in SAS

How do I print out the data type of a macro variable in the log
%macro mymacro(dt2);
%LET c_mth = %SYSFUNC(intnx(month,&dt2.d,-1,e),date9.) ;
%put &c_mth;
%mend;
mymacro('01sep2014')
I have a bunch of macro variables assigned using a %let or into:
my problem is I'm trying to do a bunch of boolean condition on dates but I suspect that some of my variables are strings and some are dates
I have casted them in my code but to triple check there is surely a way to return something to the log
I want something similar to using str() or mode() or is.numeric() in R
H,
The SAS macro language is weird. : )
As Reeza said, macro variables do not have a type, they are all text.
But, if you use Boolean logic (%IF statement), and both operands are integers, the macro language will do a numeric comparison rather than a character comparison.
So you can use the INPUTN() function to convert the date strings to SAS dates (number of days since 01Jan1960), and then compare those. Here's an example, jumping off from your code:
%macro mymacro(dt1,dt2);
%local c_mth1 c_mth2 n_mth1 n_mth2;
%let c_mth1 = %sysfunc(intnx(month,&dt1.d,-1,e),date9.) ;
%let c_mth2 = %sysfunc(intnx(month,&dt2.d,-1,e),date9.) ;
%let n_mth1 = %sysfunc(inputn(&c_mth1,date9.)) ;
%let n_mth2 = %sysfunc(inputn(&c_mth2,date9.)) ;
%put &c_mth1 -- &n_mth1;
%put &c_mth2 -- &n_mth2;
%if &n_mth1<&n_mth2 %then %put &c_mth1 is before &c_mth2;
%else %put &c_mth1 is NOT before &c_mth2;
%mend;
Log from a sample call:
236 %mymacro('01feb1960','01mar1960')
31JAN1960 -- 30
29FEB1960 -- 59
31JAN1960 is before 29FEB1960
--Q.
Macro variables do not have a type, they are all text.
You have to make sure the variable is passed in a way that makes sense to the program and generates valid SAS code.
%let date1=01Jan2014;
%let date2=31Jan2014;
data _null_;
x = "&date1"d > "&date2"d;
y = "&date2"d > "&date1"d;
z = "&date2"d-"&date1"d;
put 'x=' x;
put 'y=' y;
put 'z=' z;
run;
Log should show:
x=0
y=1
z=30
If your macro variables resolve to date literals, you can use intck combined with %eval to compare them, e.g.
%let mvar1 = '01jan2015'd;
%let mvar2 = '01feb2015'd;
/*Prints 1 if mvar2 > mvar1*/
%put %eval(%sysfunc(intck(day,&mvar1,&mvar2)) > 0);