ASSIGNMENT #2 ( *** ANSWERS ***) 1

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1 ASSIGNMENT #2 ( *** ANSWERS ***) 1 * problem #1 *** WHERE WILL THE PERMANENT SAS DATA SET BE WRITTEN libname x 'i:\' CREATE A PERMANENT SAS DATA SET NAMED CLINICAL USE AN INFILE STATEMENT TO TELL SAS WHERE THE RAW DATA ARE LOCATED USE COLUMN INPUT FOR ALL VARIABLES EXCEPT FOR VISIT (FORMATTED INPUT) YOU ARE TOLD START-END COLUMNS - IN THIS PROBLEM, IT'S EASY YO USE (EXCEPT FOR THE DATE) USE A FORMAT STATEMENT TO ASSIGN A RULE TO THE DISPLAY VISIT AS A DATE data x.clinical infile 'f:\sasclass\data\clinical.dat' id $ 1-2 group $ 11 chol sbp dbp hr typevis $ visit mmddyy8. bpratio = sbp / dbp id = 'PERSONAL IDENTIFIER' group = 'STUDY GROUP' visit = 'DATE OF VISIT' chol = 'CHOLESTEROL' sbp = 'SYSTOLIC BLOOD PRESSURE' dbp = 'DIASTOLIC BLOOD PRESSURE' hr = 'HEART RATE' typevis = 'TYPE OF VISIT' bpratio = 'SYSTOLIC/DIASTOLIC' format visit mmddyy10. bpratio 5.1 run * WHAT DOES THE DATA LOOK LIKE title 'CLINICAL DATA' proc print data=x.clinical run

2 ASSIGNMENT #2 ( *** ANSWERS ***) 2 * problem #2 YOU ONLY NEED THE COUNTY AND POPULATIONS, NOT THE GENDER YOU WERE TOLD IN CLASS THAT EACH POPULATION TOOK UP 10 COLUMNS USE FORMATTED INPUT (AND AN INFORMAT LIST FOR THE POPULATIONS) USE A SLASH IN THE INPUT STATEMENT TO READ TWO RECORDS PER COUNTY data pop95 infile county (m1-m5) (comma10.) (f1-f5) (comma10.) tot_pop = m1+m2+m3+m4+m5+f1+f2+f3+f4+f5 pct85_m = 100 * m5 / tot_pop pct85_f = 100 * f5 / tot_pop county = 'RESIDENCE COUNTY' tot_pop = 'POPULATION' pct85_m = '%85+ MALES' pct85_f = '%85+ FEMALES' run title 'NEW YORK STATE POPULATION DATA' proc print data=pop95 noobs var county tot_pop pct85_m pct85_f format tot_pop comma12. pct85_m pct85_f 5.1 run EXTRA...SINCE THE VALUES OF THE POPULATIONS ARE SPACE-DELIMITED, YOU COULD USE LIST INPUT TO READ THE POPULATIONS...YOU NEED A COLON IN THE PARENTHESES, BUT NO COLUMN WIDTH... data pop95 infile county (m1-m5) ( : comma.) (f1-f5) ( : comma.) OR YOU COULD TRY AN INFORMAT STATEMENT, COLUMN+LIST INPUT, AND RELATIVE MOVES WITH + SIGNS... data pop95 informat m1-m5 f1-f5 comma. infile 'f:\sasclass\data\nyspop95.dat' county $ m1-m5 / +4 f1-f5 FROM LATER IN THE COURSE, YOU COULD COMPUTE TOTAL POPULATION USING THE SUM FUNCTION... tot_pop = sum (of m1-m5 f1-f5)

3 ASSIGNMENT #2 ( *** ANSWERS ***) 3 * problem #3 USE LIST INPUT TO HOLD THE RECORD FOR MORE INPUT OF DATA YOU MUST DIVIDE HEIGHT BY 100 (OR THE HEIGHT SQUARED BY 10,000 data bmi subject : $2. wkg bmi = wkg / (hcm*hcm/10000) subject = 'SUBJECT NUMBER' wkg = 'WEIGHT (KILOGRAMS)' hcm = 'HEIGHT (CENTIMETERS)' bmi = 'BODY MASS INDEX' format bmi 6.1 datalines run title 'BODY MASS INDEX STUDY DATA' proc print data=bmi var subject wkg hcm bmi run EXTRA...YOU COULD HAVE WRITTEN THE BMI CALCULATION AS... bmi = wkg / (hcm/100)**2 OR YOU HAVE WRITTEN THE INPUT STATEMENT WITH AN INFORMAT FOR HEIGHT SINCE YOU CAN THINK OF HEIGHT AS HAVING IMPLIED DECIMAL PLACES, THE HEIGHT IN METERS... subject : $2. wkg hm : THEN THE BMI CALCULATION IS JUST... bmi = wkg / hm**2

4 ASSIGNMENT #2 ( *** ANSWERS ***) 4 * problem #4 * USE LIST INPUT TO HOLD THE RECORD FOR MORE INPUT OF DATA data pre_post subject : $2. prewt diffwt = postwt - prewt subject = 'SUBJECT NUMBER' prewt = 'PRE-INTERVENTION WEIGHT' postwt = 'POST-INTERVENTION WEIGHT' diffwt = 'CHANGE IN WEIGHT' datalines run title 'WEIGHT CHANGE STUDY' proc means data=pre_post var diffwt run

5 ASSIGNMENT #2 ( *** ANSWERS ***) 5 * problem #5 USE FORMATTED INPUT - SKIP TO A NEW INPUT RECORD USING A SLASH YOU MUST READ 4 RECORDS PER ZIP THERE IS AN EXTRA SLASH IN THE INPUT AFTER YOU READ RECORD #3 FIR EACH ZIP USE AN LRECL OPTION ON THE INFILE STATEMENT TO TELL SAS RECORD LENGTH > 256 data nyszip90 infile 'e:\stf3b90.dat' zip t_pop m_pop f_pop 9. grad 9. pcapinc 9. / m_pct = 100 * m_pop / t_pop f_pct = 100 * f_pop / t_pop g_pct = 100 * grad / t_pop format m_pct f_pct g_pct 5.1 t_pop m_pop f_pop comma11. pcapinc dollar12. zip = 'RESIDENCE ZIP' t_pop = 'POPULATION' m_pop = 'MALES' f_pop = 'FEMALES' grad = '# WITH GRADUATE DEGREE' pcapinc = 'PER CAPITA INCOME' m_pct = '% MALES' f_pct = '% FEMALES' g_pct = '% GRADUATE DEGREE' run

6 ASSIGNMENT #2 ( *** ANSWERS ***) 6 * problem #6 libname x 'i:\' USE FORMATTED INPUT USE INFORMAT LISTS TO READ THE DIAGNOSES AND PROCEDURES data x.hospital infile id admit disch (adx pdx odx1-odx14) (ppr opr1-opr14) dob race eth $1. age = (admit - dob) / 365 los = disch - admit format admit disch dob mmddyy10. run

7 ASSIGNMENT #2 ( *** ANSWERS ***) 1 *problem 1-1: LIST INPUT *use an INFILE statement - look for raw data in an external file data vsigns infile 'd:\sasclass\data\vital' id : $2. hr sbp dbp run *problem 1-2: LIST INPUT WITH COMMA-SEPARATED VALUES *add the DSD option to read comma-delinited data data vsigns2 infile 'd:\sasclass\spring01\data\vitalc' dsd id : $2. hr sbp dbp run *problem 1-3: LIST INPUT * control variable lengths using a colon modifier + an informat data college name : $10. title : $5. tenure : $1. number datalines Stevenson Ph.D. Y 2 Smith Ph.D. N 3 Goldstein M.D. Y 1 run *problem 1-4: LIST INPUT WITH AN AMPERSAND MODIFIER *use an AMPERSAND modifier to read a variable with embedded spaces data college2 name & : $20. title : $5. tenure : $1. number datalines George Stevenson Ph.D. Y 2 Fred Smith Ph.D. N 3 Alissa Goldstein M.D. Y 1 run *problem 1-5: COLUMN INPUT * CAN'T READ DATES WITH COLUMN INPUT data respond call_no 1-3 date : mmddyy8. trucks alarm 17 format date date9. datalines /21/ /23/ /01/ run

8 ASSIGNMENT #2 ( *** ANSWERS ***) 2 *problem 1-6: FORMATTED INPUT data call_no date trucks alarm 1. format date date9. datalines /21/ /23/ /01/ run *problem 1-7: READ SAME DATA MORE THAN ONCE data id factory state quantity price dollar7. format price dollar7. datalines 13AB2NY44 $123 22XXXCT88 $1, TX11$22,999 run *problem 1-8: READ DATA WITH AN INFORMAT LIST data ssn (score1-score10) (3.) *another way to the data * (ssn score1-score10) (comma *3.) *the format SSN can be used to display social security numbers with leadong zeroes and embedded dashes format ssn ssn. datalines run

9 ASSIGNMENT #2 ( *** ANSWERS ***) 3 *problem 1-9: USING ABSOLUTE AND RELATIVE POINTERS data (sbp1-sbp4) (3. (dbp1-dbp4) (+3 3.) datalines run *problem 1-10: USE TO HOLD A RECORD FOR INPUT *use to hold a record for subsequent data htwt infile 'd:\sasclass\data\mixed_up' emp_id $ 1-3 r_type if r_type eq 1 then height 4-5 weight 6-8 else height 5-6 weight 8-10 *EXTRA - DROP statement eliminates variable R-TYPE from the data set drop r_type run *problem 1-11: USE TO HOLD A RECORD FOR INPUT data mileage car_make $ datalines Taurus 20 Civic 29 Cutlass 20 Cadillac 17 Celica 24 Corvette 17 run *problem 1-12: USE A FILENAME STATEMENT TO CONCATENATE TWO FILES filename xxx ( 'd:\sasclass\data\file_one' 'd:\sasclass\data\file_two' ) data scores infile xxx (name score) ($10. 3.) run