/*==============================*/
/* CREATING PERMANENT DATA SETS */
/*==============================*/

    
    /*This is an option statement that identifies the data library and the
    computer directory in which to store your permanent data set*/

LIBNAME mylib 'C:/mysubdirectory'

    /*This is the first line of a data step that creates a permanent data set*/

DATA mylib.newnurse;

    /*NOTE:  The default (and temporary) library is called WORK, so you can
    refer to an ordinary temporary data set as newnurse or work.newnurse*/


/*==================================================*/
/* CREATING A NEW DATA SET BASED ON AN OLD DATA SET */
/*==================================================*/

    
    /*This is a data step command that creates a new data set called newnurse
    that recalls one already-created data set called nurseone*/

DATA newnurse;
    SET nursingl;

    /*This is a data step command that creates a new data set called newnurse that
    recalls two already-created data sets (called nurseone and nursetwo) then
    combines them as if they contain different observations from the same study*/

DATA allnurse;
    SET nursingl nursings;

    /*This is a data step command that creates a new data set called newnurse that
    recalls two already-created data sets (called nurseone and nursetwo) then
    combines them as if they contain different information about the same
    patients, each of whom have a unique patient id stored in the variable patid*/

DATA newnurse;
    MERGE nursingl nursings;
    BY PARTNERID;



/*====================================*/
/* FORMATTING AND LABELING A DATA SET */
/*====================================*/


     /*This is a data step command that labels variables*/

LABEL BEDS="number of beds in home"
      MCDAYS="annual medical in-patient days (hundreds)"
      TDAYS="annual total patient days (hundreds)"
      PCREV="annual total patient care revenue ($hundreds)"
      NSAL="annual nursing salaries ($hundreds)"
      FEXP="annual facilities expenditures ($hundreds)";
    
    /*This procedure step creates a format for the rural variable*/

PROC FORMAT;
    VALUE RURAL 0="URBAN" 1="RURAL";
    VALUE BEDS 25="SMALLEST";
RUN;

    /*This is a data step command that applies an already-created
    format to a variable - note the period following a format name*/

FORMAT RURAL RURAL.
       BEDS BEDS.;
     
/*====================================*/
/* SELECTING ONLY PARTS OF A DATA SET */
/*====================================*/

    
    /*This is a data step command that keeps only the listed variables
    in your data set - from this point on these are the only variables
    that will be available to you*/

KEEP PCREV BEDS;

    /*This is a data step command that drops the listed variables*/

DROP FEXP;

   /*This is a data step command that KEEPS only those observations that
    satisfy the test*/

IF RURAL=1;

    /*This is a data step command that DELETES only those observations that
    satisfy the test*/

IF RURAL=1 then DELETE;

    
/*========================*/
/* CREATING NEW VARIABLES */
/*========================*/

    
    /*This is a data step command that creates a variable CONST that is always 1*/

CONST=1;

    /*This is a data step command that creates a variable REVPBED from
    other variables in the data set*/

REVPBED = PCREV/BEDS;

    /*This is a data step command that creates a variable SIZE based on another
    variable in the data set*/

IF BEDS < 40 then SIZE=1;
IF BEDS >= 40 & BEDS < 120 then SIZE=2;
IF BEDS >= 120 then SIZE=3;
IF BEDS = . then SIZE=.;
    
    /*This is a data step command that does the same as above, but different syntax*/

IF BEDS = . then SIZE = .;
ELSE IF BEDS < 40 then SIZE=1;
ELSE IF BEDS < 120 then SIZE=2;
ELSE SIZE=3;