The Basics
An INFORMAT statement in a DATA step permanently associates an informat with a variable. You can specify standard SAS informats or user-written informats, previously defined in PROC FORMAT. A single INFORMAT statement can associate the same informat with several variables, or it can associate different informats with different variables. If a variable appears in multiple INFORMAT statements, SAS uses the informat that is assigned last.
你把informat x 8.2; 放在 x=12345.1234;之后，就是12345.12了。
或者直接使用format  x 8.2语句。

谢啦
这是出自哪本书呀？