CS 313001 92704

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CS 313-0019/27/04

• Recap
• Chapters 1-4
• Lab0, Lab1

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Chapter 1Introduction to COBOL and Program
Development
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Chapter 2A Complete COBOL Program

• A spacing chart or printer spacing chart is often
  used in designing reports.
• A spacing chart is divided into numbered rows and
  columns and can be a great help in the accurate
  coding of the output lines in your program.

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Overall COBOL Hierarchy Chart
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Hierarchy Chart for Tuition Billing Program
PREPARETUITIONREPORT
WRITEHEADINGLINE
READSTUDENTFILE
PROCESSSTUDENTRECORD
WRITEUNIVERSITYTOTALS
COMPUTEINDIVIDUALBILL
INCREMENTUNIVERSITYTOTALS
WRITEDETAILLINE
READSTUDENTFILE
COMPUTETUITION
COMPUTEUNIONFEE
COMPUTEACTIVITYFEE
COMPTUESCHOLARSHIP
(c) Complete Hierarchy Chart (Levels 1-4)
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COBOL Notation (Page 35)
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SWITCHES

• Switches are used in the decision-making logic of
  a program

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88 level entry

• A condition name (88-level entry) is a special
  way of writing a relational condition that makes
  it (the condition) easier to read
• Condition names are defined in the Data Division,
  then referenced in the Procedure Division.

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88-level entry continue

• The definition of a condition name in the Data
  Division simplifies subsequent coding in the
  Procedure Division.
• The use of an 88-level entry also allows multiple
  codes to be grouped under a single data name.

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Condition Names (88-level entries) Page 44
(a) Syntax
05 YEAR-CODE PIC 9. 88 FRESHMAN VALUE
1. 88 SOPHOMORE VALUE 2. 88
JUNIOR VALUE 3. 88 SENIOR VALUE 4.
88 GRAD-STUDENT VALUES ARE 5 THRU 8. 88
UNDER-CLASSMAN VALUES ARE 1, 2 88
UPPER-CLASSMAN VALUES ARE 3, 4. 88
VALID-CODES VALUES ARE 1 THRU 8. IF FRESHMAN
PERFORM WELCOME-NEW-STUDENTSEND-IF IF
VALID-CODES PERFORM PROCESS-STUDENT-RECORDEL
SE DISPLAY INCOMING YEAR CODE IS IN
ERROREND-IF.
(b) Examples
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Accumulators visit in chapter 4
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Chapter 3
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Rules of the MOVE Statement (Elementary Data
Items)
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Illustration of the MOVE statement Alphanumeric
Sending Field to Alphanumeric Receiving Field
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Table 5.3 Illustration of the MOVE statement
Numeric Sending Field to Numeric Receiving Field
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The ROUNDED Clause
DATA NAME
A B C
PICTURE 9V99 9V99 9V9
Value before execution 123
456 (immaterial) Value after execution of ADD
A B GIVING C 123 456 57 ADD A B
GIVING C ROUNDED 123 456 58
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The COMPUTE Instruction
DATA NAME
A B C COMMENTS
Value before execution 2 3
10 Initial Values Value
after execution of COMPUTE C A B.
2 3 5
Simple addition COMPUTE C A B
2. 2 3 8
Multiplication before addition
COMPUTE C (A B) 2. 2
3 10 Parenthesis
evaluated first COMPUTE C A B.
2 3 8
algebraically, c ab COMPUTE C B
A. 2 3
9 algebraically, c ba
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The COMPUTE Instruction (continued)
ALGEBRAIC EXPRESSION
COBOL COMPUTE
x a b COMPUTE X A B. x a b
COMPUTE X (A B) / 2. 2 x (a
b)c COMPUTE X (A B) C / 2.
2 x a b COMPUTE X (A B) / (2 C).
2c x ?a COMPUTE X A .5. x a?
b? COMPUTE X (A 2 B 2) / C 2
c2
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Table 5.7 The ADD Instruction
DATA NAME
A B C
Value before execution 5 10
30 Value after execution of ADD A TO C
5 10 35 ADD A B TO C 5
10 45 ADD A TO B GIVING C 5
10 15 ADD A 18 B GIVING C 5
10 33 ADD A 18 B TO C 5
10 63 ADD 1 TO B C 5
11 31
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Table 5.8 The SUBTRACT Instruction
DATA NAME
A B C D
Value before execution 5
10 30
100 Value after execution of SUBTRACT A FROM
C 5 10
25 100 SUBTRACT
A B FROM C 5
10 15
100 SUBTRACT A B FROM C GIVING D
5 10 30
15 SUBTRACT 10 FROM C D
5 10 20
90
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Table 5.9 The MULTIPLY Instruction
DATA NAME
A B C
Value before execution 5 10
30 Value after execution of MULTIPLY B BY A
GIVING C 5 10 50 MULTIPLY A
BY B GIVING C 5 10
50 MULTIPLY A BY B 5 50
15 MULTIPLY B BY A 50 10
30 MULTIPLY A BY 3 GIVING B C 5 15
15
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PROGRAMMING TIP
Use the COMPUTE Statement for Multiple
Arithmetic Operations
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Table 5.10 The DIVIDE Instruction
DATA NAME
A B C
Value before execution 5 10
30 Value after execution of DIVIDE 2
INTO B. 5 5 30
DIVIDE 2 INTO B GIVING C. 5 10
5 DIVIDE B BY 5 GIVING A
2 10 30 DIVIDE A INTO B C
5 2 6 DIVIDE A
INTO B GIVING C 5 10 2
DIVIDE 3 INTO A GIVING B REMAINDER C
5 1 2
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Table 5.11 Arithmetic on Fields with Assumed
Decimal Points
DATA NAME
A B C
PICTURE 99 99V9 99V99
Value before execution 12 345
4712 Value after execution of ADD B TO A
46 345 4712 ADD A TO B
12 465 4712 ADD B TO C 12
345 8162 ADD C TO B 12
816 4712 ADD C TO A 59
345 4712 ADD A TO C 12
465 5912
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Table 5.7 The ADD Instruction
DATA NAME
A B C
Value before execution 5 10
30 Value after execution of ADD A TO C
5 10 35 ADD A B TO C 5
10 45 ADD A TO B GIVING C 5
10 15 ADD A 18 B GIVING C 5
10 33 ADD A 18 B TO C 5
10 63 ADD 1 TO B C 5
11 31
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Table 5.8 The SUBTRACT Instruction
DATA NAME
A B C D
Value before execution 5
10 30
100 Value after execution of SUBTRACT A FROM
C 5 10
25 100 SUBTRACT
A B FROM C 5
10 15
100 SUBTRACT A B FROM C GIVING D
5 10 30
15 SUBTRACT 10 FROM C D
5 10 20
90
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Table 5.9 The MULTIPLY Instruction
DATA NAME
A B C
Value before execution 5 10
30 Value after execution of MULTIPLY B BY A
GIVING C 5 10 50 MULTIPLY A
BY B GIVING C 5 10
50 MULTIPLY A BY B 5 50
15 MULTIPLY B BY A 50 10
30 MULTIPLY A BY 3 GIVING B C 5 15
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