有效使用范围:DATA Step 。参考:Statements: RETAIN Statement - 9.2 (sas.com) Without a RETAIN statement, SAS automatically sets variables that are assigned values by an INPUT or assignment statement to missing before each iteration of the DATA step. The RETAIN statement causes the values of all v...
SET reads all variables and all observations from the input data sets unless you tell SAS to do otherwise. A SET statement can contain multiple data sets; a DATA step can contain multiple SET statements. 2. RETAIN的作用:对于数据集中新声明的变量,SAS会在data步循环执行开始时将其置为空值,而如...
Why does the retain statement have that second effect on only created numeric variables when using it to reorder variables in a data step? The RETAIN statement is designed to RETAIN the values of variable from one iteration to the next. That is not a "side-effect". The side effect is wha...
In this paper I will focus on the RETAINstatement, but with an eye toward certain general properties of the SAS DATA step. Looking at the DATA step from the perspective of a particular statement allows for an immediate, and concrete, grasp of what otherwise might feel like a rather abstract...
sasretain用法sasretain用法 The basic syntax of RETAIN statement is as follows: RETAIN <variable 1> <variable 2>…<variable n>; Where, <variable 1><variable 2>…<variable n> are the variables whose values have to be maintained through out the iteration of the Data Step. When the RETAIN ...
SAS Retain Statement A Retain statement tells the SAS that it does not set the missing values assigned to the variables during each data step iteration. Instead, it will specify the variable names which sustain and retain the values of all the variables created in the Input or assignment statem...
If a value appears in a RETAIN statement, variablesthat appear before it in the list are initially set to that value. If different initial values areassigned to the same variable by naming it more than once in a RETAIN statement, SAS uses the last value.Yi Zhao...
set sashelp.class(keep = _numeric_); *只读入数值型变量; run; drop语句的用法和keep一样,套着用就行,另外drop=选项的效率也高于drop语句。 retain语句《不可执行的语句》retains values from the previous iteration of the DATA step 这个比较重要了,我先解释下sas的运行机制 sas的data步和run语句之间其实...
retain语句《不可执行的语句》retains values from the previous iteration of the DATA step 这个比较重要了,我先解释下sas的运行机制 sas的data步和run语句之间其实是一个循环,比如当使用set语句的时候,每次set一条观测,一直运行到run;再返回程序开头,继续set第二条观测值,一直将数据集的观测值读取完。
A datastep is a block of SAS code starting "Data ...;" and ending "run;". I assume what you mean here is that you want to check the previous 5 records, or observations as they are called in SAS. You can keep values by using the RETAIN statement. The problem here is though that...