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Contents. Data Movement verb. Arithmetic Verbs. Sequence Control Verbs. Input and Output Verbs. Conditional Verb: IF CATEGORIES OF COBOL STATEMENTS. DATA MOVEMENT VERB. It is possible to move data from one place in the memory to another place.

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Contents

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  1. Contents • Data Movement verb. • Arithmetic Verbs. • Sequence Control Verbs. • Input and Output Verbs. • Conditional Verb: IF • CATEGORIES OF COBOL STATEMENTS.

  2. DATA MOVEMENT VERB • It is possible to move data from one place in the memory to another place. • This is done with the help of the MOVE verb. There are, • Numeric MOVE • Nonnumeric or alphanumeric MOVE • To perform a MOVE operation ,the PIC clauses of both fields must be identical.

  3. MOVE Statement • MOVE identifier-1 TO identifier-2 • Copies contents of identifier-1 To identifier-2 • identifier-1 is sending field • identifier-2 is receiving field FORMAT 1

  4. MOVE Statement Example • Move Qty-In To Qty-Out • Contents of Qty-Out replaced by contents of Qty-In • If Qty-In = 253, contents of Qty-Out = 253 after MOVE executed • Qty-In remains unchanged Example

  5. MOVE Statement • MOVE literal-1 TO identifier-2 • Value of literal-1 copied to identifier-2 • Data type of literal and identifier should match • Move numeric literals to numeric fields • Move nonnumeric literals to alphanumeric fields FORMAT 2

  6. MOVE Statement Examples • 05 Qty-Out Pic 999.05 Color-Out Pic X(4). Move 100 To Qty-Out Move 'Blue' To Color-Out • Contents of Qty-Out replaced with 100 • Contents of Color-Out replaced with 'Blue' Examples

  7. Multiple Moves • MOVEidentifier-1TO identifier-2 …literal-1 Move 0 To Total-1, Total-2, Total-3 • Move may have multiple receiving fields • Contents of all three total fields set to 0 Full Format

  8. Moving Figurative Constants • ZEROS may be moved to numeric or alphanumeric field • Moves 0 to every position of receiving field • SPACES moved only to alphanumeric field • Moves space or blank to every position of receiving field. MOVE ZEROS TO TOTAL-OUT.

  9. Numeric MOVE • Numeric field or literal is moved to numeric receiving field • When PIC clauses of both fields identical, sending and receiving fields same after MOVE • Previous contents of receiving field are replaced by MOVE

  10. Numeric MOVE Rules • Decimal alignment always maintained • If 86.52 is moved to a field • 86 always treated as integer part of number • .52 always treated as decimal part of number • Digits in integer part moved right to left starting at decimal point • Digits in decimal part moved left to right starting at decimal point

  11. Numeric MOVE Example • Operation: Move Amt-1 To Amt-2Amt-1Amt-2 Picture 99V99 Picture 99V99 Contents 12^34 Contents 67^89 • Digits in integer part moved so that • 2 replaces 7, 1 replaces 6 • Digits in decimal part moved so that • 3 replaces 8, 4 replaces 9

  12. Numeric MOVE Example • Operation: Move Amt-1 To Amt-2Amt-1Amt-2 Picture 99V99 Picture 99V99 Contents 12^34 Contents 67^89 • After MOVE, contents of Amt-2 = 12^34

  13. Numeric MOVE Rules • If receiving field has more integer positions than sending field • Unfilled high-order (leftmost) integer positions filled with zeros • If receiving field has more decimal positions than sending field • Unfilled low-order (rightmost) decimal positions filled with zeros

  14. Numeric MOVE Example • Operation: Move Amt-3 To Amt-4Amt-3Amt-4 Picture 9V9 Picture 99V99 Contents 3^4 Contents 56^78 • Digits in integer part moved so that • 3 replaces 6, 0 replaces 5 • Digits in decimal part moved so that • 4 replaces 7, 0 replaces 8

  15. Numeric MOVE Example • Operation: Move Amt-3 To Amt-4Amt-3Amt-4 Picture 9V9 Picture 99V99 Contents 3^4 Contents 56^78 • After MOVE, contents of Amt-4 = 03^40

  16. Numeric MOVE Rules • If receiving field has fewer integer positions than sending field • High-order (leftmost) digits truncated • If receiving field has fewer decimal positions than sending field • Low-order (rightmost) digits truncated

  17. Numeric MOVE Example • Operation: Move Amt-5 To Amt-6Amt-5Amt-6 Picture 99V99 Picture 9V9 Contents 12^34 Contents 5^6 • Digits in integer part moved so that 2 replaces 5, 1 not moved • Digits in decimal part moved so that 3 replaces 6, 4 not moved

  18. Numeric MOVE Example • Operation: Move Amt-5 To Amt-6Amt-5Amt-6 Picture 99V99 Picture 9V9 Contents 12^34 Contents 5^6 • After MOVE, contents of Amt-6 = 2^3

  19. Nonnumeric MOVE • Sending field is alphanumeric field or nonnumeric literal • Receiving field is alphanumeric field

  20. Rules for Nonnumeric MOVE • Characters moved from left to right • If receiving field longer, low-order (rightmost) positions replaced with spaces • If receiving field shorter, low-order characters in sending field truncated

  21. Nonnumeric MOVE Example • Operation: Move Code-1 To Code-2Code-1Code-2 Picture X(3) Picture X(6) Contents abc Contents mnopqr • Characters abc replace mno • Remaining three positions in Code-2 replaced with blanks

  22. Nonnumeric MOVE Example • Operation: Move Code-3 To Code-4Code-3Code-4 Picture X(5) Picture X(3) Contents vwxyz Contents efg • Characters vwx replace efg • y and z are not moved since all positions in Code-4 are filled

  23. Group Moves • When receiving field is group item, alphanumeric MOVE rules followed • If subfields are numeric, invalid data may be stored in subfields

  24. Group Move Example • Operation: Move "ABCD" To WS-Code 01 WS-Code. 05 WS-Part-1 Pic XX. 05 WS-Part-2 Pic 99. • After MOVE, value of WS-Part-1 is AB, WS-Part-2 is CD • Causes error if WS-Part-2 then used in arithmetic operation

  25. MOVE Operations • Avoid using sending field with different data type than receiving field • Move numeric fields, numeric literals or ZEROS to numeric fields • Move alphanumeric fields, nonnumeric literals, ZEROS or SPACES to alphanumeric fields

  26. Basic Arithmetic Verbs • ADD, SUBTRACT, MULTIPLY, DIVIDE COMPUTE • All require fields operated on to • Have numeric PICTURE clauses • Contain numeric data when statements executed

  27. ADD … TO Statement identifier-1 ADD … TO identifier-2 ... literal-1 • identifier-1 or literal-1 added to identifier-2 • Result stored in identifier-2 Format 1

  28. ADD … TO Examples Assume X, Y and Z are numeric fields X = 5, Y = 3 and Z = 7 ADD StatementResult Expression Add X To Y Y = 8 Y=X+Y Add X, 9 To Y Y = 17 Y=X+9+Y Add X, 6, Y To Z Z = 21 Y=X+6+Y+Z

  29. ADD … TO Statement • Identifiers preceding TO are unchanged • Value of identifier after TO • Used in ADD operation • Original value replaced with ADD result

  30. ADD … GIVING Statement identifier-1 ADD … GIVING identifier-2 ... literal-1 • Identifiers and literals preceding GIVING added together • Result stored in identifier-2 Format 2

  31. ADD … GIVING Examples Assume X, Y and Z are numeric fields X = 5, Y = 3 and Z = 7 ADD StatementResultExpression Add X, Y Giving Z Z = 8 Z=X+Y Add X, 10 Giving Y Y = 15 Y=X+10 Add X, 4, Y Giving Z Z = 12 Z=X+4+Y

  32. ADD … GIVING Statement • Identifiers preceding GIVING are unchanged • Value of identifier after GIVING • Not part of ADD operation • Original value replaced with ADD result • May be report-item with edit symbols

  33. ADD … GIVING Statement • TO may be included before last identifier or literal preceding GIVING • For example: Add X, 4 To Y Giving Z • Adds values of X, 4 and Y together • Stores result in Z

  34. ADD Statement • Comma followed by one space may be used to separate operands • Result of ADD always placed in field(s) after TO or GIVING • Result field must be data-name, not a literal

  35. Producing More Than One Sum • Several ADD operations can be done in single statement • Assume X, Y and Z are numeric fields X = 5, Y = 3 and Z = 7 ADD StatementResult Add X To Y, Z Y = 8, Z = 12 Add X, 6 Giving Y, Z Y = 11, Z = 11

  36. ADD … TO vs ADD … GIVING • Use ADD … TO when original contents of result operand • Need to be included in operation • But are not needed after operation • Use ADD … GIVING when • Original contents of all operands except result field are to be retained

  37. SUBTRACT Statement identifier-1 SUBTRACT … FROM identifier-2 ... literal-1 • identifier-1 or literal-1 subtracted from identifier-2 • Result stored in identifier-2 Format 1

  38. SUBTRACT Examples Assume A, B and C are numeric fields A = 6, B = 2 and C = 18 SUBTRACT StatementResult Subtract A From C C = 12 C=C-A Subtract B, 5 From C C = 11 C=C-(B+5) Subtract B From A, C A = 4, C = 16 A=A-B C=C-B

  39. SUBTRACT Statement Rules • All identifiers and literals must be numeric • Data-name, not a literal, must follow FROM • All fields, literals preceding FROM added together • Sum subtracted from field after FROM • Result stored in field after FROM

  40. SUBTRACT … GIVING Statement identifier-1 identifier-2 SUBTRACT … FROM literal-1 literal-2 GIVING identifier-3 ... • identifier-1 or literal-1 subtracted from identifier-2 or literal-2 • Result stored in identifier-3 Format 2

  41. SUBTRACT … GIVING Examples Assume A, B and C are numeric fields A = 6, B = 2 and C = 18 SUBTRACT StatementResult Subtract B From A Giving C C = 4 Subtract A From 15 Giving C C = 9 Subtract A, 4 From C Giving B B = 8 B=C-(A+4)

  42. SUBTRACT … GIVING Rules • All identifiers, literals before FROM must be numeric • GIVING must be followed by data-name • May be numeric or report-item • All fields, literals preceding FROM added together • Sum subtracted from field after FROM • Result stored in field after GIVING

  43. MULTIPLY Statement identifier-1 MULTIPLYBY identifier-2 ... literal-1 • identifier-1 or literal-1 multiplied by identifier-2 • Result stored in identifier-2 Format 1

  44. MULTIPLY Examples Assume Q, R and S are numeric fields Q = 4, R = 7 and S = 5 MULTIPLY StatementResult Multiply Q By R R = 28 R=R*Q Multiply 10 By S S = 50 S=10*S Multiply 2 By R, S R = 14, S = 10 R=2*R, S=S*2

  45. MULTIPLY … GIVING Statement identifier-1 identifier-2 MULTIPLYBY literal-1 literal-2 GIVING identifier-3 ... • identifier-1 or literal-1 multiplied by identifier-2 or literal-2 • Result stored in identifier-3 Format 2

  46. MULTIPLY … GIVING Examples Assume Q, R and S are numeric fields Q = 4, R = 7 and S = 5 MULTIPLYStatementResult Multiply Q By R Giving S S = 28 Multiply Q By 3 Giving S S = 12 Multiply 6 By Q Giving R, S R = 24 S = 24

  47. MULTIPLY Statement • Only two operands can be multiplied • To obtain product of 3 operands requires two instructions To find Price x Qty x Discount Multiply Price By Qty Giving Amt Multiply Discount By Amt

  48. DIVIDE Statement identifier-1 DIVIDEINTO identifier-2 ... literal-1 • identifier-1 or literal-1 divided into identifier-2 • Result stored in identifier-2 Format 1

  49. DIVIDE Examples Assume X, Y and Z are numeric fields X = 2, Y = 12 and Z = 8 DIVIDEStatementResult Divide X Into Y Y = 6 Y=Y/X Divide 3 Into Y Y = 4 Y=Y/3 Divide 2 Into Y, Z Y = 6, Z = 4 Y=Y/2, Z=Z/2

  50. DIVIDE … GIVING Statement identifier-1 INTO identifier-2 DIVIDE literal-1 BY literal-2 GIVING identifier-3 ... • identifier-1 or literal-1 divided into or by identifier-2 or literal-2 • Result stored in identifier-3 Format 2

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