Replace the values of set one by values from set two using PROC FORMAT

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Suppose we have data set one and two as below:

one has variable a and two has variable b;

a=(1 2 3)

b=(x y z)

What we want to do is, if we have a new data set expressed in numerical values,

we want to change its numerical numbers 1, 2, 3 to character x, y, z .

For example, if we have

x=(1 2 3 5 7 9), we want to have y as

y=(x y z 5 7 9).

Or generally, replace the values of data set one by the values of data set two.

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data one;

  input a;

  cards;

  1

  2

  3

  ;

run;

data two;

   input b $;

   cards;

   a

   b

   c

   ;

run;

data fmtds;

   merge one two;

   rename a=start b=label;

   end=a;

   fmtname='newfmt';

run;

proc print data=&syslast;

run;

proc format library=work cntlin=fmtds;

run;

data test;

   input x;

   y=put(x,newfmt.);

   cards;

   1

   2

   3

   4

   5

   6

   ;

run;

proc print data=&syslast;

run;

/*******************************************************

The result is shown as below:

                        Obs    x    y

                         1     1    a

                         2     2    b

                         3     3    c

                         4     4    4

                         5     5    5

                         6     6    6

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A useful paper to read:
10 things to know about proc format
10 thinks to know about proc format