COBOL Initialize Statement: A Complete Guide.

COBOL Initialize Statement.

Introduction.

In COBOL programs, the Initialize statement plays a crucial role in initializing data items within a program. By utilizing the Initialize clause, programmers can efficiently set the initial values of variables, arrays, or groups of data elements. This blog post goes through the syntax, provides examples, explores common errors, and highlights the key function of the COBOL Initialize statement.

Definition: COBOL Initialize clause is used to initialize the values of the variable. The easiest way to use this statement is to code it without the Replacing clause and to refer to a group item. Then, all the numeric fields in the group are set to zeros, and all the alphabetic and alphanumeric fields are set to spaces. However, if you code the Replacing Clause, you can specify which type of fields you want to change, and you can specify the characters that you want those fields to be initialized with. 

COBOL Initialized Clause Syntax:

The syntax of the COBOL Initialize statement is as follows:

INITIALIZE identifier-1 [REPLACING category-name BY value-1 [, category-name BY value-2 ...]]

• identifier-1 is the name of the data item or group item to be initialized.
• REPLACING is an optional keyword that can be used to specify that the values of the data items should be replaced with the values specified in the BY clause.
• category-name is the name of the category of data to be initialized. The following categories are supported:

• ALPHABETIC
• ALPHANUMERIC
• ALPHANUMERIC-EDITED
• DBCS
• EXTERNAL FLOATING-POINT
• INTERNAL FLOATING-POINT
• NATIONAL
• NATIONAL-EDITED
• NUMERIC
• NUMERIC-EDITED
• value-1 is the value to be assigned to the data item.
• , is a comma used to separate multiple BY clauses.

The function of the COBOL Initialize Clause:

The primary function of the COBOL Initialize clause is to reset or initialize data items to predefined values before their usage in a program. By using this clause, programmers can ensure that variables, arrays, or groups have a predictable starting state, preventing any inconsistencies or accidental use of residual values.

By employing the REPLACING clause within the Initialize statement, developers can selectively replace specific portions of a data item with desired values. This selective initialization offers flexibility and allows for more efficient initialization of complex data structures.

COBOL Initialize Clause Examples:

Let's explore a few examples to understand the practical usage of the COBOL Initialize clause: 

• The following example initializes the WS-RECORD data item to all spaces:

INITIALIZE WS-RECORD

• The following example initializes the WS-NUMBER data item to 100 and the WS-NAME data item to "John Doe":

INITIALIZE WS-RECORD REPLACING NUMERIC DATA BY 100 ALPHANUMERIC DATA BY "John Doe"

 

Initializing an Array by using COBOL Initialize Statement.

Consider an array, "customer-names," which stores the names of 10 customers. To initialize all elements of this array to blank spaces, we can use the Initialize clause like this:

01 customer-names OCCURS 10 TIMES.

   05 name PIC X(20).

...

INITIALIZE customer-names.

The Initialize statement ensures that all elements of the customer-names array are set to spaces, allowing for proper utilization when storing customer names later in the program.

Common Errors with the COBOL Initialize Clause.

While using the COBOL Initialize clause, programmers may encounter some common errors. These errors can be easily avoided with careful attention to detail. Here are a few examples:

• Omitting the target-identifier: It is essential to specify the correct data item or group that requires initialization. Forgetting to mention the target-identifier in the Initialize statement will result in errors.
• Inconsistent data types: Ensure that the data type of the target-identifier matches the replacement value if provided. Mismatched data types can lead to unexpected behavior or compilation errors.
• Misplaced or incorrect REPLACING clause: When using the REPLACING clause, verify that the replacement values and their positions are correctly defined. Incorrect specifications may lead to undesired results or syntax errors.

COBOL Initialize Statement Performace Tuning Tip.

Programmers typically use the initialize verb to initialize copybooks and temporary variables before executing the business logic. Although the COBOL-initialized verb is easy to use, it can have a significant impact on program performance. For example, if you carelessly initialize a 50,000-byte table that doesn't need to be initialized, it can significantly slow down your program.

Conclusion.

The COBOL Initialize statement is a powerful tool that allows COBOL programmers to initialize data items effectively. By using the Initialize clause, developers can set the initial values of variables, arrays, or groups, providing a clean starting point for their programs.

►Subscribe to Topictrick & Don't forget to press THE BELL ICON to never miss any updates. Also, Please visit mention the link below to stay connected with Topictrick and the Mainframe forum on - 

► Youtube

► Follow us on Twitter  

► Facebook 

► Linkedin

► Reddit

► Mainframe Blog

► Medium Blog

Thank you for your support. 

Mainframe Forum™

Created with Artisteer