SAS--chapter12（ SAS 数据集的读写）

　　

libname clinic 'D:sas';
data lab23.drug1h(drop=placebo uric);
set research.cltrials(drop=triglyc);
if sex='M' then delete;
if placebo='YES';
TestDate='22MAY1999'd;
retain Days 30;
days+1;
length Retest $ 5;
if cholesterol>190 then retest='YES';
else if 150<=cholesterol<=190 then retest='CHECK';
else if cholesterol<150 then retest='NO';
label retest='Perform Cholesterol Test 2?';
format enddate mmddyy10.;
run;

data clinic.data1017(drop=sex);
    set sasuser.diabetes(keep=age sex);  *想根据if筛观测单位，又不想要这个变量，drop和keep必须都要有sexif sex='F';　　　　　　　　　　　　　　　　*如果只有drop有sex，dara2017里只有一个变量名，无observation;
run;

*proc sort  out  by （排序）
print by  （subtotal）
data by （排序）;
proc sort data=clinic.data1016 out=data;
by height;
run;
data data1;
    set data;
    by height;   *by之前，该变量必须已经被排序了??//有一个appropriate index;
run;

* 查看一个单位;
data data2;
    obsnum=5;
    set clinic.admit point =obsnum;
    output;   *没有output和stop，无限循环；有stop，无output，空数据集；;
            *有output无stop，无限多个第五观察值;
run;            *输入文件会有一个end-of-file marker，但是point指定了一个变量，则没有这个marker，所以需要stop;

data data3 data4;    *同时创建两个data set ，只有output中的data有内容;
    set clinic.admit;
    output data3;
run;

data data5;
    set clinic.admit end=last;  *读累加后变量（he）的最后一个值=总计;
    he+height;                    *end 和point不能在同一step;
    we+weight;
    fe+fee;
    if last;
run;

proc sort data=company.usa out=work.temp2;
        by manager jobtype;
     data company.budget2(keep=manager jobtype payroll);
        set work.temp2;
        by manager jobtype;
        if wagecat='S' then Yearly=wagerate*12;
        else if wagecat='H' then Yearly=wagerate*2000;
        if first.jobtype then Payroll=0;
        payroll+yearly;
        if last.jobtype;
     run;

     data work.getobs5(drop=obsnum);
        obsnum=5;
        set company.usa(keep=manager payroll) point=obsnum;
        output;
        stop;
     run;

     data work.addtoend(drop=timemin timesec);
        set clinic.stress2(keep=timemin timesec) end=last;
        TotalMin+timemin;
        TotalSec+timesec;
        TotalTime=totalmin*60+timesec;
        if last;
     run;

 libname clinic 'c:stresslabdata';
     options nodate number pageno=15;
     proc sort data=clinic.stress out=work.maxrates;
        by maxhr;
     run;
     proc print data=work.maxrates label double noobs;
        id name;
        var resthr maxhr rechr date;
        where tolerance='I' and resthr>90;
        sum fee;
        label rechr='Recovery HR';
     run;
     title 'August Admission Fees';
     footnote 'For High Activity Patients';
     proc print data=clinic.admit label;
        var actlevel fee;
        where actlevel='HIGH';
        label fee='Admission Fee';
        format fee dollar4.;
     run;