This post explains how to count number of missing (blanks) and non missing (non blank) values across multiple columns. It's very easy to calculate it with SAS. It's one of the common data manipulation task that SAS programmers deal in a day to day task but it is mostly associated with finding number of rows or number of non-missing values across rows. There is a rule in SAS that we should remember - We use PROCs when we need to aggregate a COLUMN. Whereas, we use FUNCTIONs to aggregate a row.

The program below creates a sample dataset which would be named as

The SAS function

*Let's create a sample data for demonstration -*The program below creates a sample dataset which would be named as

**TEMP**and it would be stored in**WORK**library.data temp;

input x y z a b$;

cards;

1 23 24 50 AA

1 . 24 50 AC

1 13 . 50 AB

1 23 . 50 .

;

run;

*The sample data looks like below -*Sample Data |

**Count Missing and Nonmissing NUMERIC Values**The SAS function

**N**calculates the number of non-blank**numeric**values across multiple columns. To count the number of missing numeric values, you can use**NMISS**function.data outdata;

set temp;

nvalues =N(of x--a);

nmiss =nmiss(of x--a);

proc print;

run;

Output |

**Note -**The N(of x--a) is equivalent to N(x, y, z, a). In this case, we are not using the variable b in the above program.

**Count total missing and nonmissing values**

Suppose you need to calculate number of both character and numeric non-missing and missing values.

Since SAS has no inbuilt function to calculate the number of variables, we need to use

The function

Since SAS has no inbuilt function to calculate the number of variables, we need to use

**PROC CONTENTS**to calculate the number of variables. Later we are storing the number of variables information in a macro variable which is**totvar**.

**CMISS Function**The function

**CMISS**counts the number of missing values across columns. It considers missing values of both numeric and character variables.proc contents data=temp out=cols noprint;

run;

data _null_;

set cols nobs=total;

call symputx('totvar', total);

run;

data outdata;

set temp;

totalvar=&totvar;

totmiss=cmiss(of x--b);

totnonmiss=totalvar- cmiss(of x--b);

proc print ;

run;

SAS : Output |

In the above program, there are 4 observations, and NOBS is used to calculate the number of observations, so how can we calculate number of variables. I mean when we use "set cols nobs=total;" the value of total should be 4 and the value of &totvar should also be 4, but in output it is showing 5. How? I am confused.

ReplyDeleteThis comment has been removed by the author.

DeleteHey, it is because out statement in proc contents will create a new dataset with the number of variables as number of observation.

ReplyDeleteHi if I want to list out the names of variables missing by each row how can I do that?

ReplyDeleteHow can we find number of Null values in all the columns and rows. Also, find the percentage of Null values in each

ReplyDeletecolumn. Round off the percentages upto two decimal places