| SAS Companion for the OpenVMS Environment |
The default
length of numeric variables in SAS data sets is 8
bytes. (You can change the length of SAS numeric variables
with the LENGTH statement in the DATA step.) In the SAS System under OpenVMS Alpha,
the data type of numeric variables is IEEE double precision or T_FLOATING.
The precision of an OpenVMS Alpha T_FLOATING value
is expressed as 15 decimal digits, with a range for T_FLOATING numeric
variables of 1.7E+308 to 2.3E-308.
In addition, with Alpha
T_FLOATING numbers,
you can specify a minimum length of 3 bytes using the LENGTH statement in
the DATA step. However, with VAX D_FLOATING numbers,
the minimum length you can specify is 2
bytes.
Significant Digits and Largest Integer for SAS Variables in the Alpha Environment
shows the number of nontruncated significant digits and largest integers that
can be represented exactly with no loss of precision for each of the specified
lengths.
Significant Digits and Largest Integer for SAS Variables in the Alpha Environment
|
Length in Bytes |
Significant Digits Retained |
Largest Integer Represented Exactly |
|
3 |
3 |
8,191 |
|
4 |
6 |
2,097,151 |
|
5 |
8 |
536,870,911 |
|
6 |
11 |
137,438,953,471 |
|
7 |
13 |
35,184,372,088,831 |
|
8 |
15 |
9,007,199,254,740,991 |
For more information about
converting
2-byte numeric
variables from VAX environments to 3-byte numeric
variables for use in Alpha environments, see the procedure VAXTOAXP.
Copyright © 1999 by SAS Institute Inc., Cary, NC, USA. All rights reserved.
