An_introduction_to_SAS__Part_2_ - An Introduction to SAS...

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An Introduction to SAS data patientdata; input id $ gender $ age height weight pre_bp post_bp; cards; B23 M 55 72 165 145 120 C32 F 63 64 123 165 132 C19 M 68 78 160 162 145 D55 M 70 73 240 180 165 A96 M 64 71 255 155 134 B11 F 73 63 180 151 143 A08 F 59 . 175 172 141 E49 M 61 75 210 149 129 A77 F 82 63 162 166 130 E05 F 69 65 151 165 139 ; run; data patientdata2; set patientdata; average_score = (pre_bp + post_bp)/2; diff_score = pre_bp - post_bp; weight_kg = weight*0.4536; height_m = height/39.37; bmi = weight_kg/(height_m**2); log_bmi = log(bmi); if id='D55' then age=71; if 0 <= bmi < 18.5 then delete; if bmi >= 30 then obese = 'Y'; else obese = 'N'; if age <= 55 then age_group=1; else if 55 < age <= 65 then age_group=2; else if age > 65 then age_group=3; drop weight height; run; proc print data=patientdata2; run; We now continue learning SAS programming by building off of this program and adding a variety of SAS procedure statements. SAS Procedures SAS statements that request predefined routines are called procedures . SAS procedures are the means by which we will examine and analyze the data. All procedures have the same basic syntax: proc procname options; statement / statement options; statement / statement options; run;
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The word proc is followed by the name of the procedure. In this SAS statement, we may also include one or more options, many of which are specific to the SAS procedures being used. The most common option specifies the data set to be used within the procedure. If this is not specified, the default data set to be used is the one most recently created. We begin with one of the simplest procedures, proc print , which was used in the first part. Proc Print This procedure prints the data for a given working data set. proc print data=patientdata2; run; The above statement will print all variables in the data set patientdata2 . It is often desired to print only a subset of the variables contained in the data set especially in cases where the data set is made up of many variables. This may be done by use of a var statement. If we wish to print only the id and bmi variables from our data set, we use the statements, proc print data=patientdata2; var id bmi; run; It is often a good idea to print the working data set a few times as data is manipulated in order to verify SAS is doing what we think it is. Proc Sort This procedure serves the purpose of sorting a given data set by one or more of the variables within the data set in ascending order (smallest to largest). The sorting variable(s) are specified using a by statement. If the key word descending is put in front of a sort variable, the order of sorting is reversed for that particular variable.
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An_introduction_to_SAS__Part_2_ - An Introduction to SAS...

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