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Tables 1

TABLES () group of storage locations (i.e. elements) with the same name accessed by name and subscript ex. var-name (sub) similar to arrays in other languages

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Tables 4

TABLE examplesIdentifier used with OCCURS may also be group item

01 Tax-Table.05 Group-X Occurs 20 Times.

10 City Pic X(6).10 Tax-Rate Pic V999.

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Tables 5

EXAMPLE #101 DAYS-OF-MONTH-TABLE.

03 MONTHS OCCURS 12 times.05 Month-Name PIC X(15).05 Month-Num-Days PIC 99.

Move January to Month -Name (1)Move 31 to Month-Num-Days (1)

EXAMPLE #2 01 DAYS-OF-MONTH-TABLE.

05 Month-Name PIC X(15) OCCURS 12 TIMES.

05 Month-Num-Days PIC 99 OCCURS 12 TIMES.Move January to Month -Name (1)Move 31 to Month-Num-Days (1)

More TABLE examples

How else initialize

Month-Name andMonth-Num-Days?!

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Tables 6

01 GRADE-TABLE.05 QUIZ-TABLE OCCURS 40 TIMES.

10 QUIZ1 PIC 9(2).10 QUIZ2 PIC 9(2).10 QUIZ3 PIC 9(2).10 QUIZ4 PIC 9(2).

How do we average all the quiz scores for QUIZ4? Compute-Average-Quiz4.

MOVE ZERO TO Total-GradeMOVE 1 TO SubPERFORM UNTIL Sub > Num-Quizzes

ADD QUIZ4(Sub) TO Total-Grade ADD 1 TO SubEND-PERFORMDIVIDE Total-Grade BY Num-Quizzes

GIVING Average-Score

One More TABLE example

***Convert toPerform-Varying

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Tables 7

Two ways to use VALUE clause to initialize all elements to zero:01 Array-1 Value Zero.

05 Totals Occurs 50 Times Pic 9(5).01 Array-1.

05 Totals Occurs 50 Times Pic 9(5) Value Zero.

Can also initialize each element to different value

01 Day-Names Value 'SUNMONTUEWEDTHUFRISAT'.05 Days Occurs 7 Times Pic X(3).??? Can an initialization be done on the 05 directly above???

INITIALIZE STATEMENT (i.e. in Procedure Division)

A series of elementary items contained within a group item can all beinitialized. Numeric items will be initialized to zero and nonnumericitems will be initialized to blank.

FORMAT: INITIALIZE {identifier- 1}

INITIALIZING TABLES

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Tables 8

REDEFINESPurpose : Used to define a field with a value clause then redefine it as an array.However, you cannot do the reverse; that is, once an entry has been defined byan OCCURS clause, it may NOT be redefined.

FORM T in Data Division :L# identifier-1 REDEFINES identifier-2 [finish declaration]

where:L# means level number

Identifier-1 and identifier-2 must be on the same level

EX MPLES:See table example program

01 Rates.

05 10Rate PIC 99V999 value 12.345.05 100Rate REDEFINES 10Rate PIC 999V99.05 1000Rate REDEFINES 10Rate PIC 9999V9.

Result 100Rate = 123.45 and 1000Rate = 1234.5

01 HoldDate.02 amerDate.

03 amerDay PIC 99 value 11.03 amerMonth PIC 99 value 3.03 amerYear PIC 9(4) value

2014

CanDate REDEFINES AmerDate.03 CanMonth PIC 99.03 CanDay PIC 99.03 CanYear PIC 9(4).

canMonth = 3 and CanDay = 11

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Tables 9

Define array as follows:01 Temperature-Array.

05 Day-In-Week Occurs 7 Times.10 Hour Occurs 24 Times.

15 Temp Pic 9(3).

2 dimensional TABLES (ex#1)For your information :If reading in from file, what does input filelook like?!

FD input file01 input-rec pic 999.

Find the average temp for: each day.

Find the average temp for each hour.

PARTICIPATION POINTS (5)

(due in one week graded on if works!)

What if have negative temperatures?How solve?! That is, what does input filelook like? What does declaration looklike?

Perform a from 1 by 1 until a > 7

perform b from 1 by 1 until b > 24

read input-file at end..

move input-rec to temp (a b)

end-perform

End-perform

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Tables 10

2 dimensional TABLES (ex#2)01 Jeans-Table.

05 Jean-Gender OCCURS 2 TIMES.10 Jean-Color OCCURS 3 TIMES.

15 Jean-SalesValue PIC 9(8)V99.15 Jean-NumSold PIC 9(7).

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Tables 11

2 dimensional TABLES (ex#3)

01 Jeans-Table.

05 Jean-Size OCCURS 10 TIMES.10 Exact-Size PIC 99.10 Jean-Style PIC X.10 Jean-Color OCCURS 3 TIMES.

15 Jean-SalesValue PIC 9(8)V99.15 Jean-NumSold PIC 9(7).

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REDEFINES

01 MONTH-NAMES.

05 STRING-1 PIC X(15)

VALUE JANFEBMARAPRMAY.

05 MONTH REDEFINES STRING-1

OCCURS 5 TIMES PIC XXX.

MOVE MONTH(3) TO MONTH-OUT

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Referencing a Table01 TABLE.

05 TABLE-ENTRY OCCURS 10 TIMES.10 NUM PIC 99.10 NAME PIC X(30).10 ITEM PIC X(5) OCCURS 3 TIMES.

COBOL tables are 1-indexedSome valid References with subscripts:

TABLE-ENTRY(SUB)

TABLE NUM(SUB) NAME(SUB)

ITEM(SUB1,SUB2)

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Subscripts vs Indexes Subscripts are defined separately from the table

definitions.01 MYTABLE.

05 ITEM PIC X(3) OCCURS 10 TIMES.

01 I PIC 9(4) BINARY....

MOVE 1 TO I

MOVE ABC TO ITEM(I)

Subscripts are numeric fields choose BINARY fields forefficiency, although packed and zoned fields also work

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Subscripts vs Indexes

Subscripts can be easily printed01 MYTABLE.

05 ITEM PIC X(3) OCCURS 10 TIMES.

01 I PIC 9(4) BINARY.

...

MOVE 1 TO I

MOVE ABC TO ITEM(I)

DISPLAY I

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Subscripts vs Indexes

Subscripts represent an occurrence number, 1 isthe first occurrence, 2 is the second,

01 MYTABLE.

05 ITEM PIC X(3) OCCURS 10 TIMES.

01 I PIC 9(4) BINARY.

...

PERFORM VARYING I FROM 1 BY 1 UNTIL I > 10

DISPLAY ITEM(I)END-PERFORM

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Subscript Program

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Subscripts vs Indexes Indexes are created when a table is defined

01 MYTABLE.

10 LETTERVALS PIC X(10) VALUE 'ABCDEFGHIJ'.

10 LETTER REDEFINES LETTERVALSPIC X(1) OCCURS 10 TIMES

INDEXED BY I.

Indexes are manipulated with SET statements andautomatically altered by PERFORM statements

SET I TO 1

MOVE LETTER(I) TO CHAROUT

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Subscripts vs Indexes

Indexes are generally more efficient than subscripts

Indexes represent offsets from the beginning of the tableSET I TO 1

Causes I to have the binary value 0 internally.

It takes a bit of work to print them

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Index Program

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Tables with Two Dimensions01 TABLE.

05 TABLE-ENTRY OCCURS 10 TIMESINDEXED BY SUB1.

10 NUM PIC 99.10 NAME PIC X(30).

10 ITEM PIC X(5) OCCURS 3 TIMESINDEXED BY SUB2.

Valid References with subscripts:TABLE-ENTRY(SUB1)

TABLE NUM(SUB1) NAME(SUB1)

ITEM(SUB1,SUB2)

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Subscripts and Indexes

In a two-dimensional table, the two subscriptscorrespond to the row and column numbers.

In a three-dimensional table, the threesubscripts correspond to the depth, row, andcolumn numbers.

Indexes use address computation to efficientlyreference items in a table.