where clause not working

[Anna_nag]

Hi all,

I am working on this program which is giving me outputs for some observations and null values for others. The programs works for values until 1.3 and after that does not produce a output.

Please try putting 1.3 (which works) and 1.4 (doesn't work) in where statement of proc sql.

Data A;

do x =0.1 to 100not working by 0.1;

output ;

end;

run;

proc sql;

select * from A where x = 1.4; /* Try the values of 1.3 and 1.4 */

quit;

[Tom · Accepted solution]

This is caused by the fact that computers store numbers in floating point binary numbers.  You cannot represent 1/10th exactly using binary digits.  So eventually you see a difference between adding 0.1 multiple times and normal representation of the same number.  Use the ROUND() or test for a very small absolute difference instead.

Data _null_;

do x =0.1 to 2 by 0.1;

if x in (1.3,1.4) then put x= 'Not rounded';

if round(x,0.1) in (1.3,1.4) then put x= 'Rounded' ;

end;

run;

[Anna_nag]

Thanks!!