the meaning "From" and "To"?

AprilRush

Hi, Could anyone tell me the meaning "From" and "To"?

Thanks.

DATA COMPU;

SET OLDCOM;

ARRAY C[&TIMEPTS] C1-C&TIMEPTS;

ARRAY TT[&Timepts] TT1-TT&Timepts;

ARRAY GC[&TIMEPTS] GC1-GC&TIMEPTS;

DO I=1 TO &TIMEPTS;

IF TT LT FROM OR TT GT TO THEN GC=.;

ELSE GC=C;

END;

RUN;

路斯菲尓

LT 和GT 后面应该跟的都是变量名或是数值……

不好意思，学艺不精，太高深了，搞不懂！