What does lag function do in SAS?

In SAS, the LAG function is used to compare the current value to its predecessors. If you want to calculate lag of second order, use LAG2 function. Similarly, you can use LAG3 function for measuring lag of third order.

How do I use the Keep function in SAS?

The KEEP statement cannot be used in SAS PROC steps. The KEEP= data set option can. The KEEP statement applies to all output data sets that are named in the DATA statement. To write different variables to different data sets, you must use the KEEP= data set option.

How does lag work in SQL?

SQL Server LAG() is a window function that provides access to a row at a specified physical offset which comes before the current row. In other words, by using the LAG() function, from the current row, you can access data of the previous row, or the row before the previous row, and so on.

Why we use retain statement in SAS?

The RETAIN statement simply copies retaining values by telling the SAS not to reset the variables to missing at the beginning of each iteration of the DATA step. If you would not use retain statement then SAS would return missing at the beginning of each iteration. The retain statement keeps the value once assigned.

How do I keep only certain columns in SAS?

To write different columns to different tables, you must use the KEEP= table option. The DROP statement is a parallel statement that specifies columns to omit from the output table. The KEEP and DROP statements select columns to include in or exclude from output tables. The subsetting IF statement selects rows.

What is a RETAINed variable?

A variable which is RETAINed (or implicitly. RETAINed – see below) will keep the same value through any. number of DATA step iterations, unless and until that value is. explicitly changed (e.g. by assignment, or data read with. INPUT, SET etc.).

How do I restrict observations in SAS?

You can use the OBS= and FIRSTOBS= data set options to limit the number of observations that SAS processes. The OBS= data set option specifies the number of the last observation to process. It does not specify how many observations should be processed.

What is Intnx function?

The INTNX function returns the SAS date value for the beginning date, time, or datetime value of the interval that you specify in the start–from argument. (To convert the SAS date value to a calendar date, use any valid SAS date format, such as the DATE9.