对两列之间的行进行求和

时间:2016-07-08 15:20:33

标签: sum sas datastep

我的数据看起来像这样,我无法弄清楚如何获得“想要”列。我已经尝试了保留,滞后和求和函数的各种组合,但遗憾的是没有成功。

month   quantity1   quantity2   want
1       a           x           x+sum(b to l)
2       b           y           sum(x to y)+sum(c to l)
3       c           z           sum(x to z)+sum(d to l)
4       d       
5       e       
6       f       
7       g       
8       h       
9       i       
10      j       
11      k       
12      l       

感谢您对此事的任何帮助

3 个答案:

答案 0 :(得分:2)

将quantity1相加然后将值存储到宏变量很方便。使用多余的'数据示例:

proc sql;
   select sum(qty1) into:sum_qty1 from temp;
quit;

data want;
   set temp;
   value1+qty1;
   value2+qty2;
   want=value2+&sum_qty1-value1;
   if missing(qty2) then want=.;
   drop value:;
run; 

答案 1 :(得分:1)

您可以一步完成此操作,但以下内容会产生两个所需的结果。第一步是计算相关quantity1值的总和,第二步是将它们添加到相关quantity2值的总和中:

 data temp;
    input month qty1 qty2;
    datalines;
        1 1 100
        2 1 100
        3 1 100
        4 1 .
        5 1 .
        6 1 .
        7 1 .
        8 1 .
        9 1 .
        10 1 .
        11 1 .
        12 1 .
    ;
run;

proc sql;
    create table qty1_sums as select distinct
        a.*, sum(b.qty1) as qty1_sums
        from temp as a
        left join temp as b
        on a.month < b.month
        group by a.month;

    create table want as select distinct
        a.*,
        case when not missing(a.qty2) then sum(a.qty1_sums, sum(b.qty2)) end as want
        from qty1_sums as a
        left join temp as b
        on a.month >= b.month
        group by a.month;
quit;

答案 2 :(得分:1)

听起来像一个滚动12个月的总和&#39;如果是这样,使用不同的数据结构更容易(不是2个变量,而是24行1变量);那么你就拥有了所有的ETS工具,或SQL或SAS数据步骤中的简单过程。

如果您无法重构数据,那么您可以通过将数据加载到临时数组(或哈希表,但数组对于新手来说更简单)来实现。这使您可以直接访问整个事物。例如:

data have;
  do month = 1 to 12;
    q_2014 = rand('Uniform')*10+500+month*5;
    q_2015 = rand('Uniform')*10+550+month*5;
    output;
  end;
run;

data want;
  array q2014[12] _temporary_;       *temporary array to hold data;
  array q2015[12] _temporary_;
  if _n_=1 then do;                  *load data into temporary arrays;
    do _n = 1 to n_data;
      set have point=_n nobs=n_data;
      q2014[_n] = q_2014;
      q2015[_n] = q_2015;
    end;
  end;
  set have;
  do _i = 1 to _n_;                          *grab the this_year data;
    q_rolling12 = sum(q_rolling12,q2015[_i]);
  end;
  do _j = _n_+1 to n_data;
    q_rolling12 = sum(q_rolling12,q2014[_j]);*grab the last_year data;
  end;
run;
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