如何让 SAS 忘记小数位 i 变量？

Question

I have a problem with decimal places in my SAS-variables.

I have two numeric variables which I want to compare in SAS. They are both formatted with numx10.1 and one of the variables is calculated like this:

avg(delay)/30.44 as delay_months  format=numx10.1

I want to compare the two values in a datastep using

where var1^=delay_months ;

But even thought both variables have the same value for example. 4,1, SAS still shows this observation in the datastep with the where-statement . I guess it is because of the decimals in the delay_months variable.

How can I get SAS to forget the decimal places and only focus on the number I see - for example 4,1?

Answer 1

Format does not change the value - it is only the way SAS represents it to you. One suggestion could be rounding during comparison (or when you create the variables)

where round(var1, 0.1) ^= round(delay_months, 0.1);

SAS uses floating-point representation for numeric values. Because of that sometimes what you see is not what it is. More about that in SAS documentation