topic Re: Dynamic apply format by making the fmtname from a value in the same dataset in SAS Programming

Dynamic apply format by making the fmtname from a value in the same dataset

RB1Kenobi — Thu, 23 Feb 2017 11:33:51 GMT

Hello

I am using SAS9.4 on a Windows10 PC environment.

I am trying to create a string column to contain a full description by using a format within a PUT statement. I want the format name to be generated dynamically based on a value in a different column. This seems feasible but I can't quite nail it, example program attached.

I have this problem on a couple of programs so all help will be gratefully received, thank you.

Re: Dynamic apply format by making the fmtname from a value in the same dataset

Kurt_Bremser — Thu, 23 Feb 2017 11:42:29 GMT

Not possible.

The format is set when the data step is compiled, so formats need to be named literally.

From the documentation of the put() function:

format.

contains the SAS format that you want applied to the value that is specified in the source. This argument must be the name of a format with a period and optional width and decimal specifications, not a character constant, variable, or expression.

(Emphasis by me)

Read the documentation.

Re: Dynamic apply format by making the fmtname from a value in the same dataset

RW9 — Thu, 23 Feb 2017 11:44:53 GMT

Post your examples as text in a code window ({i} above post). Is there a reason you want to try to automate it, you will need to have the list somewhere if so. If its just a couple then what you have is fine. To automate will take more code:

data fmts;
  length fmt_cond fmt $200;
  input fmt_cond $ fmt $;
datalines;
A1 $fmt2
A2 $fmt1
;
run;

data _null_;
  set fmts  end=last;
  if _n_=1 then call execute('data want;  set have;');
  call execute('if variable="'||strip(fmt_cond)||'" then res=put(   ...);
  if last then call execute('run;');
run;

Just as an example, however I would really question why this is necessary at all.

Re: Dynamic apply format by making the fmtname from a value in the same dataset

Reeza — Thu, 23 Feb 2017 14:15:59 GMT

PUTC/PUTN allow format names that are from a variable.

Borrowing code:

data fmts;
length fmt_cond fmt $200;
input fmt_cond $ fmt $;
datalines;
A1 $fmt2
A2 $fmt1
;
run;

Data want;

set fmts;

want_var = putc(fmt_cond, fmt);

Run;

Re: Dynamic apply format by making the fmtname from a value in the same dataset

mkeintz — Thu, 23 Feb 2017 15:12:02 GMT

I suspect you would also be well served by a hash lookup table, keyed on 2 vars: PRODTYPE and DISCOUNT. Make a lookup dataset, with all the expected combinations of prodtype,discount, and discount_desc. Then load it into a hash object to use in the data step:

data lookup;
  input  prodtype :$2. discount :$1. @6 discount_desc $30.;
datalines;
A1 A this was discount $10
A1 B this was discount $20
A2 A this was discount $300
A2 B this was discount $400
run;

data demo_description_dynamic (drop=rc);
  set demodata;
  if _n_=1 then do;
    if 0 then set lookup;
    declare hash h (dataset:'lookup');
      h.definekey('prodtype','discount');
      h.definedata(all:'Y');
      h.definedone();
  end;
  rc=h.find();
  if rc^=0 then call missing(discount_desc);
run;

When the h.find() method is successful, two things happen: RC=0 and discount_desc is retrieved from the desired item in hash object h. If it's unsuccessful, RC ^=0 and discount_desc is unchanged from the last successful h.find(). That's why you see discount_desc set to missing when rc^=0.

Re: Dynamic apply format by making the fmtname from a value in the same dataset

rogerjdeangelis — Thu, 23 Feb 2017 21:08:34 GMT

/* T1002580 Using putc or putn with format names in your data

Using putc or putn with format names in your data

This seems to work

inspired by
https://goo.gl/ktxY1O
https://communities.sas.com/t5/Base-SAS-Programming/Dynamic-apply-format-by-making-the-fmtname-from-a-value-in-the/m-p/335244

HAVE
====

proc format;
      value $ FMTA1X
      "A" = "this was discount $10"
      "B" = "this was discount $20"
      ;

      value $ FMTA2X
      "A" = "this was discount $300"
      "B" = "this was discount $400"
            ;
run;

Up to 40 obs WORK.HAVE total obs=5

Obs    PRODTYPE    DISCOUNT

 1        A1          B
 2        A2          A
 3        A2          A
 4        A2          B
 5        A1          B

WANT
====

Up to 40 obs WORK.DEMO_DESCRIPTION_HARDCODE total obs=5

Obs    PRODTYPE    DISCOUNT        DISCOUNT_DESC

 1        A1          B        this was discount $20   putc(discount,$fmta1x.)
 2        A2          A        this was discount $300
 3        A2          A        this was discount $300
 4        A2          B        this was discount $400
 5        A1          B        this was discount $20


SOLUTION
========

data have;
input Prodtype $ Discount $;
cards4;
A1 B
A2 A
A2 A
A2 B
A1 B
;;;;
run;quit;

data want;
  retain prodtype discount discount_desc;
  length discount_desc $44;
  set have;

  fmt=cats('$fmt',prodtype,'x');
  Discount_desc = putc(Discount,fmt);

run;quit;


Up to 40 obs WORK.WANT total obs=5

Obs    PRODTYPE    DISCOUNT        DISCOUNT_DESC           FMT

 1        A1          B        this was discount $20     $fmtA1x
 2        A2          A        this was discount $300    $fmtA2x
 3        A2          A        this was discount $300    $fmtA2x
 4        A2          B        this was discount $400    $fmtA2x
 5        A1          B        this was discount $20     $fmtA1x

Re: Dynamic apply format by making the fmtname from a value in the same dataset

RB1Kenobi — Fri, 24 Feb 2017 10:45:50 GMT

Thank you all for your contributions.

The other way I was looking at the problem was to use create a function (Proc FCMP) which would have been stored in one place and then reference across the different programs.