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Wednesday, April 1, 2009

COBOL Tutorials

Tutorial Description
An Essay – The history of Cobol Grace Hopper, the inventor of FLOW-MATIC is the mother of the Cobol language. She built the world’s first A-0 compiler, the MATH-MATIC and FLOW-MATIC pseudo-languages, that laid the foundation for Cobol.
Introduction to Cobol Programming Learn to write simple Cobol programs, compile and link a program and run your programs.
Declaring data in Cobol Declare and use Cobol variables. The concepts of how data items are internally represented in computer-memory, and what DISPLAY and COMP usage implies are explained.
Line Sequential files Declare a Sequential file in a Cobol program. Pick up how you can read and write data from a Line Sequential file.
Working storage Variables in the working storage are used to store intermediate results of processing. They are like a rough-work sheet.
Basic Procedure Division Verbs Learn about Data Transfer or assignment of values to variables using the MOVE verb. MOVE CORRESPONDING option is also described.
Arithmetic Operators You can perform arithmetic in Cobol. There are five standard arithmetic verbs ADD, SUBTRACT, MULTIPLY,DIVIDE and COMPUTE.
Tutorial 08 – USAGE Clause
- What is USAGE Clause
- USAGE is DISPLAY
- USAGE IS COMP/BINARY
- USAGE IS COMP-1/COMP-2
- USAGE IS COMP-3
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Tutorial 09 – Decision Making in COBOL 
- Basic IF Statement
- IF ELSE Construct
- Nested Conditionals
- Types of Conditions – Class, Relational, Sign
- Complex Conditions – Boolean AND, OR, NOT
- 88-level Special conditionals
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Tutorial 10 – Program Flow Control 
- Basic PERFORM Statement
- PERFORM multi-paragraph Procedure
- PERFORM a SECTION
- PERFORM loops
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Tutorial 11 – EVALUATE Statement – I
- EVALUATE and WHEN Clause 
- Multiple Subjects and corresponding objects
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Tutorial 12 – EVALUATE Statement – II
- Agreement of the subjects with the objects
- Values that subject and object can take
- Concrete example of EVALUATE Clause
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Looping Constructs  
Arrays Declaring an array, storing and accessing data from an array. Learn how to create a pre-filled array. Two-dimensional arrays are an extension of 1-D arrays.
String-handling
Cobol’s built-in intrinsic functions
Sorting and merging data
File processing
Variable Blocked Files in Cobol
Calling sub-programs
Compile-time Errors  
Run-time errors S0C1, S0C4 and S0C7  

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