topic Re: Length issue for numeric variables in SAS Programming

Length issue for numeric variables

pavank — Fri, 05 Jul 2024 06:16:14 GMT

data digits_split;
infile datalines missover;
length digits 255;
input digits ;
datalines;
1234567899999999999999999999999999999999
5547
3324
120
1005
11
2
;
run;
Hi Experts,

can you please explain variable length 3-8 even if I have given explicit length for digits variable how to get complete digits without convert numeric to char and what is max numeric length in SAS

Re: Length issue for numeric variables

Kurt_Bremser — Fri, 05 Jul 2024 07:24:34 GMT

SAS numbers are always stored in 8 bytes floating point. For storage in datasets, this length can be reduced down to 3 bytes, but during processing it's always 8.

The maximum precision because of this is between 15 and 16 decimal digits, which is sufficient for all kinds of statistical analysis.

Anything which needs more precision is most likely not a number, but some kind of a code and must be stored as character.

Re: Length issue for numeric variables

Kurt_Bremser — Fri, 05 Jul 2024 07:44:10 GMT

PS the technical details of 8 byte floating point can be found here

Re: Length issue for numeric variables

ChrisNZ — Fri, 05 Jul 2024 12:23:52 GMT

Also to note:

SAS numbers are always stored in 8 bytes floating point

Not only SAS, that's true for numbers in software running on PC or unix.

can you please explain variable length 3-8

The length of 8 represents the number of bytes used to store the number (sign, mantissa and exponent), not the number of digits.