| Functions and CALL Routines |
Checks the validity of a character string for use as a SAS variable
name.
|
NVALID(string<,validvarname>)
|
-
string
-
specifies a character constant, variable,
or expression which will be checked to determine whether its value can be
used as a SAS variable name.
Note: Trailing blanks are
ignored. ![[cautionend]](../../../../common/63294/HTML/default/images/cautend.gif)
| Tip: |
Enclose a literal string
of characters in quotation marks. |
-
validvarname
-
is a character constant, variable, or expression
that specifies one of the following values:
|
V7 |
determines that string is a valid SAS variable name when all three of the following
are true:
-
It begins with an English letter or an underscore.
-
All subsequent characters are English letters,
underscores, or digits.
-
The length is 32 or fewer alphanumeric
characters.
|
|
ANY |
determines that string is a valid SAS variable name if it contains 32 or fewer characters
of any type, including blanks. |
|
NLITERAL |
determines that string is a valid SAS variable name if it is in the form of a SAS
name literal ('name'N) or if it is a valid SAS variable name when VALIDVARNAME=V7.
| See: |
V7 above in this same list. |
|
| Default: |
If no value is specified,
the NVALID function determines that string is
a valid SAS variable name based on the value of the SAS system option VALIDVARNAME=. |
The NVALID function checks the value of string to determine whether it can be used as a SAS variable
name.
The NVALID function returns a value of 1 or 0.
|
Condition |
Returned Value |
|
string can be used as a SAS variable name |
1 |
|
string cannot be used as a SAS variable
name |
0 |
This example determines the validity of specified strings
as SAS variable names. The value that is returned by the NVALID function varies
with the validvarname argument. The value of 1 is returned when the string
is determined to be a valid SAS variable name under the rules for the specified
validvarname argument. Otherwise, the value of 0 is returned.
options validvarname=v7 ls=64;
data string;
input string $char40.;
v7=nvalid(string,'v7');
any=nvalid(string,'any');
nliteral=nvalid(string,'nliteral');
default=nvalid(string);
datalines;
Tooooooooooooooooooooooooooo Long
OK
Very_Long_But_Still_OK_for_V7
1st_char_is_a_digit
Embedded blank
!@#$%^&*
"Very Loooong N-Literal with """N
'No closing quotation mark
;
proc print noobs;
title1 'NLITERAL and Validvarname Arguments Determine';
title2 'Invalid (0) and Valid (1) SAS Variable Names';
run;
Determining the Validity of SAS Variable Names with NLITERAL
NLITERAL and Validvarname Arguments Determine 1
Invalid (0) and Valid (1) SAS Variable Names
string v7 any nliteral default
Tooooooooooooooooooooooooooo Long 0 0 0 0
0 0 0 0
OK 1 1 1 1
Very_Long_But_Still_OK_for_V7 1 1 1 1
1st_char_is_a_digit 0 1 1 0
Embedded blank 0 1 1 0
!@#$%^&* 0 1 1 0
"Very Loooong N-Literal with """N 0 0 1 0
'No closing quotation mark 0 1 0 0
Copyright © 2011 by SAS Institute Inc., Cary, NC, USA. All rights reserved.
