sas lag 使用

data look_back;
input time temperature;
Diff_tmp=dif(temperature);
datalines;
1 60
2 62
3 65
4 70
 ;
run;
proc print data=look_back;
run; 

运行结果

Obs	time	temperature	Diff_tmp
1	1	60	.
2	2	62	2
3	3	65	3
4	4	70	5