Using external files with your SAS jobs requires that you specify filenames with
syntax that is appropriate to your operating environment. See the SAS
documentation for your operating environment for more information.
Types of Data
Definitions
data values
are character or numeric values.
numeric value
contains only numbers, and sometimes a decimal point, a minus sign, or both. When
they are read into a SAS data set, numeric values are stored in the floating-point
format native to the operating environment. Nonstandard numeric values can contain
other characters as numbers; you can use formatted input to enable SAS to read
them.
character value
is a sequence of characters.
standard data
are character or numeric values that can be read with list, column, formatted, or
named input. Examples of standard data include:
• ARKANSAS
• 1166.42
nonstandard data
is data that can be read only with the aid of informats. Examples of nonstandard data
include numeric values that contain commas, dollar signs, or blanks; date and time
values; and hexadecimal and binary values.
Numeric Data
Numeric data can be represented in several ways. SAS can read standard numeric values
without any special instructions. To read nonstandard values, SAS requires special
instructions in the form of informats. Table 19.2 on page 432 shows standard,
nonstandard, and invalid numeric data values and the special tools, if any, that are
required to read them. For complete descriptions of all SAS informats, see SAS Formats
and Informats: Reference.
Table 19.1 Reading Standard Numeric Data
Data Description Solution
23
input right aligned None needed
23
input not aligned None needed
23
input left aligned None needed
Types of Data 431
Data Description Solution
00023
input with leading zeros None needed
23.0
input with decimal point None needed
2.3E1
in E notation, 2.30 (ss1) None needed
230E-1
in E notation, 230x10 (ss-1) None needed
-23
minus sign for negative
numbers
None needed
Table 19.2 Reading Nonstandard Numeric Data
Data Description Solution
2 3
embedded blank COMMA. or BZ.
informat
- 23
embedded blank COMMA. or BZ.
informat
2,341
comma COMMA. informat
(23)
parentheses COMMA. informat
C4A2
hexadecimal value HEX. informat
1MAR90
date value DATE. informat
Table 19.3 Reading Invalid Numeric Data
Data Description Solution
23 -
minus sign follows number Put minus sign before number
or solve programmatically. It
might be possible to use the
S370FZDTw.d informat, but
positive values require the
trailing plus sign (+).[
..
double instead of single
periods
Code missing values as a
single period or use the ??
modifier in the INPUT
statement to code any invalid
input value as a missing
value.
J23
not a number Read as a character value, or
edit the raw data to change it
to a valid number.
432 Chapter 19 • Reading Raw Data
Remember the following rules for reading numeric data:
• Parentheses or a minus sign preceding the number (without an intervening blank)
indicates a negative value.
• Leading zeros and the placement of a value in the input field do not affect the value
assigned to the variable. Leading zeros and leading and trailing blanks are not stored
with the value. Unlike some languages, SAS does not read trailing blanks as zeros by
default. To cause trailing blanks to be read as zeros, use the BZ. informat described
in SAS Formats and Informats: Reference.
• Numeric data can have leading and trailing blanks but cannot have embedded blanks
(unless they are read with a COMMA. or BZ. informat).
• To read decimal values from input lines that do not contain explicit decimal points,
indicate where the decimal point belongs by using a decimal parameter with column
input or an informat with formatted input. See the full description of the INPUT
statement in SAS Formats and Informats: Reference for more information. An
explicit decimal point in the input data overrides any decimal specification in the
INPUT statement.
Character Data
A value that is read with an INPUT statement is assumed to be a character value if one
of the following is true:
• A dollar sign ($) follows the variable name in the INPUT statement.
• A character informat is used.
• The variable has been previously defined as character. For example, a value is
assumed to be a character value if the variable has been previously defined as
character in a LENGTH statement, in the RETAIN statement, by an assignment
statement, or in an expression.
Input data that you want to store in a character variable can include any character. Use
the guidelines in the following table when your raw data includes leading blanks and
semicolons.
Table 19.4 Reading Instream Data and External Files Containing Leading Blanks and
Semicolons
Characters in the Data What to Use Reason
leading or trailing blanks that
you want to preserve
formatted input and the
$CHARw. informat
List input trims leading
and trailing blanks from a
character value before the
value is assigned to a
variable.
semicolons in instream data DATALINES4 or CARDS4
statements and four
semicolons (;;;;) to mark the
end of the data
With the normal
DATALINES and CARDS
statements, a semicolon in
the data prematurely
signals the end of the data.
Types of Data 433
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