INPUT Statement, Named

Reads data values that appear after a variable name that is followed by an equal sign and assigns them to corresponding SAS variables

Valid: in a DATA step

Category: File-handling

Type: Executable

Syntax

INPUT < pointer-control > variable = <$> <@ @@>;

INPUT < pointer-control > variable = informat. <@@@>;

INPUT variable =<$> start-column < ” end-column >

<. decimals > <@ @@>;

Arguments

pointer-control

moves the input pointer to a specified line or column in the input buffer.
See: Column Pointer Controls on page 1247 and Line Pointer Controls on page 1249

variable =

names a variable whose value is read by the INPUT statement. In the input data record, the field has the form
```
  variable  =  value  
```
Featured in: Example 1 on page 1275

indicates to store a variable value as a character value rather than as a numeric value.
Tip: If the variable is previously defined as character, $ is not required.
Featured in: Example 1 on page 1275

informat.

specifies an informat that indicates the data type of the input values, but not how the values are read.
Tip: Use the INFORMAT statement to associate an informat with a variable.
See: Chapter 5, Informats, on page 927
Featured in: Example 1 on page 1275

start-column

specifies the column that the INPUT statement uses to begin scanning in the input data records for the variable. The variable name does not have to begin here.

” end-column

determines the default length of the variable.

holds an input record for the execution of the next INPUT statement within the same iteration of the DATA step. This line-hold specifier is called trailing @ .
Restriction: The trailing @ must be the last item in the INPUT statement.
Tip: The trailing @ prevents the next INPUT statement from automatically releasing the current input record and reading the next record into the input buffer. It is useful when you need to read from a record multiple times.
See: Using Line-Hold Specifiers on page 1253

holds an input record for the execution of the next INPUT statement across iterations of the DATA step. This line-hold specifier is called double trailing @ .
Restriction: The double trailing @ must be the last item in the INPUT statement.
Tip: The double trailing @ is useful when each input line contains values for several observations.
See: Using Line-Hold Specifiers on page 1253

Details

When to Use Named Input Named input reads the input data records that contain a variable name followed by an equal sign and a value for the variable. The INPUT statement reads the input data record at the current location of the input pointer. If the input data records contain data values at the start of the record that the INPUT statement cannot read with named input, use another input style to read them. However, once the INPUT statement starts to read named input, SAS expects that all the remaining values are in this form. See Example 1 on page 1275.

You do not have to specify the variables in the INPUT statement in the same order that they occur in the data records. Also, you do not have to specify a variable for each field in the record. However, if you do not specify a variable in the INPUT statement that another statement uses (for example, ATTRIB, FORMAT, INFORMAT, LENGTH statement) and it occurs in the input data record, the INPUT statement automatically reads the value. SAS writes a note to the log that the variable is uninitialized .

When you do not specify a variable for all the named input data values, SAS sets _ERROR_ to 1 and writes a note to the log. For example,

 data list;     input name=$ age=;     datalines;  name=John age=34  gender=M  ;

The note written to the log states that GENDER is not defined and _ERROR_ is set to 1.

Restrictions

Once you start to read with named input, you cannot switch to another input style or use pointer controls. All the remaining values in the input data record must be in the form variable=value . SAS treats the values that are not in named input form as invalid data.
If named input values continue after the end of the current input line, use a slash (/) at the end of the input line. This tells SAS to move the pointer to the next line and to continue to read with named input. For example,
```
 input name=$ age=; 
```
can read this input data record:
```
 name=John /     age=34 
```
If you use named input to read character values that contain embedded blanks, put two blanks before and after the data value, as you would with list input. See Example 2 on page 1275.
You cannot reference an array with an asterisk or an expression subscript.

Examples

Example 1: Using Named Input with Another Input Style

This DATA step uses list input and named input to read input data records:

 options yearcutoff= 1920;  data list;     input id name=. gender=$;     informat dob ddmmyy8.;     datalines;  4798  gender=m name=COLIN age=23 dob=16/02/75  2653 name=MICHELE age=46 gender=f  ;

The INPUT statement uses list input to read the first variable, ID. The remaining variables NAME, GENDER, and DOB are read with named input. These variables are not read in order. The $20. informat with NAME= prevents the INPUT statement from truncating the character value to a length of eight. The INPUT statement reads the DOB= field because the INFORMAT statement refers to this variable. It skips the AGE= field altogether. SAS writes notes to the log that DOB is uninitialized, AGE is not defined, and _ERROR_ is set to 1.

Example 2: Reading Character Variables with Embedded Blanks

This DATA step reads character variables that contain embedded blanks with named input:

 data list2;     informat header . name .;     input header= name=;     datalines;  header=  age=60 AND UP  name=PHILIP  ;

Two spaces precede and follow the value of the variable HEADER, which is AGE=60 AND UP . The field also contains an equal sign.