PROGRAMMING 3 QUIZ 1

COBOL

• Developed in 1959 by the CODASYL committee

• Still widely used in business, insurance, and government systems

• Remains the backbone of mainframe computing and essential for the global economy

• It is simple, portable, and maintainable but is wordy, has rigid format and not for scientific use

1960

• COBOL’s first compilers got released

1968

• It is when the first standard version of cobol was released

1974

• The second version was released and was made for efficiency

1985

• Cobol got enhanced had more versatility and structure

2002

• Object-oriented features got added to cobol

2014

• Method overloading got introduced to cobol

Machine Dependent, Easy to understand, Easy to maintain, Uniquely organized in 4 divisions, can handle voluminous data using few statements

Features of cobol language

Uses english like syntax, Unusual lenght, Column sensitive, spacing sensitive, uses indentation

Features of cobol program

Abend

• An unexpected or abnormal termination of the program due to some problem in code or data

Syntax

• It is a system-defined standard that should be followed while coding the cobol statements like MOVE, IF, PERFORM, etc.

Character String

• It is a set of characters used to name something

Statement

• It is a synthetically valid combination of words and characters written in the procedure division of cobol program and beginning with a verb.

• Individual instructions or commands in COBOL, like MOVE, ADD, DISPLAY, etc.

Sentence

• It refers to the group of statements ending in a period 

Paragraph

• It is a set of statements that are coded together separately from procedure division to perform a task

Section

• It is a set of paragraph that are coded together separately from the procedure division

Division

• Major parts used to code the cobol program

• Consists of one or more paragraph or section

Identification, Environment, Data, Procedure

Four major divisions in a cobol program

Separator

• These are characters that are used to separate strings

Delimiter

• It is used to specify the start or the end of the strings

Condition

• It is the expression that results in True or False 

• Based on the return value, the program flow gets decided

Variable

• It is a data name used to hold the value for processing in the program

• It holds a pointer to the memory location where the value is actually stored

• These are defined and declared in the data division

• These must be prepared so they can be recognized in the procedure division

Constant

• It is a variable that has only one value throughout the execution of the program

Figurative Constants

• These are system-defined keywords with predefined values

Literal

• It is the value that is assigned to the variable

Scope terminator

• It is a cobol reserved word that specifies the end of the specific cobol statements

Arithmetic Expressions

• It is the coding form of arithmetic calculations and it is a combination of two or more variables with arithmetic operators

Physical file

• It is the actual file that contains the data in the form of records

Logical file

• It is a named used in the program that refers the actual physical file

Array

• It is a set of similar elements arranged in sequential order and can access with the position

• It is called a table in COBOL 

Binary Search

• It is an algorithm used on sorted arrays to search the element quickly

• Uses the technique of repeatedly dividing the entire array into two parts until it finds the element

Compiler

• It is a utility that converts source code into object code

Load modules

• It is an executable component of the program that is generated by the compiler

Character

• Lowest form in the paragraph structure

Word

• It is made up of one or more characters

Clause

• Consists of characters and words, and is used to specify an attribute of an entry

Identification Division

• The first division of the COBOL program

• Contains the identification of the program and its author or programmer

• The function of this division is to supply information about the program to others who may use it as reference

• Its purpose is to identify the program and its author and to provide other general information about the program, such as the dates the program is written, any program security, etc.

Environment Division

• It describes the computing environment of the program

• This division describes the types of hardware in which the program is written and executed

• It supplies information about the computer equipment used in the program

• Contains the Configuration section and the Input and output section

Configuration Section

• It supplies the information about the computer on which the cobol program will be compiled and executed

• Provides documentation information which includes the computer manufacturer, computer number, and computer number model

• This defines the source and the object computer

Source Computer

• The computer that will be used for compiling the program

Object computer

• The computer that will be used for executing or running the program

Special Names

• A third paragraph that is optional in the configuration section 

• This focuses on special used for reading or displaying data

Input and output section

• Defines the files to be used in the program

• starts with the FILE-CONTROL paragraph, which uses SELECT statements

• Includes input file, where the source data is stored for processing, and the output file, where the report or result file is stored.

Data division

• This contains the file section which declares the logical input and output file to be used in the program and the working storage section which declares all the variables to be used in the program

File section

• declares the logical input and output files to be used in the program

Working storage section

• This is where all the variables to be used in the program are declared.

Procedure Division

• This division contains used defined section, paragraphs, clauses, and statements

• This is where the problem logic is developed

Cobol Coding Sheet

• It specifies from where each statement coding should start and how it differentiates from other statements

Sequence Number Area

• Columns 1-6

• Cobol compiler does not consider these columns part of the code

• Is divided in 2 parts: Page number (column 1-3), which represents the current page number and line number (4-6), which represents the current line number on the page.

Indicator Area

• It is the column 7 in the coding sheet split

Continuation Line

• uses “-” symbol

• Used to continue any sentence, entry, clause or phrase in Area B of the next line that is neither a comment or a blank line

Comment Line

• Uses “*“ symbol

• It can be written anywhere in area A and B of that line and can consists of any combination of characters from the character set of the computer

Forward slash

• Uses “/“ symbol

• Used to go to the top of the next page when printing a report

Area A

• Columns 8-11

• Contains division headers, section headers, paragraph headers or paragraph names, level indicators, declarative and end declaratives, and end program, end class, and end method markers.

Area B

• Columns 12-72

• Contains the entries, sentences, statements, and clauses

• Also contains the continuation lines

System Generated Number

• Columns 73-80

• Gets excluded by the cobol compiler during compilation time

User-defined words and reserved words

2 types of words

User-defined words

• Any word that is defined by the developer and it is used to store the data

• It can have a maximum length of 30 bytes

Reserved words

• It is a system-defined word with proper meaning or task assigned in COBOL language

• It can be keywords, optional words, figurative constants, special character words and special registers

Non-numeric and numeric

2 types of Literals

Non-numeric Literal

• Are strings enclosed by quotation marks or apostrophes

• It can contain all valid characters that are allowed by COBOL

Numeric Literals

• It is a number that is a combination of a sign and a decimal point

• Coded directly without quotation marks and apostrophes

Numeric, Alphanumeric, Figurative

3 types of constants

Alphanumeric constants

• Alphanumeric variables with only one value throughout the program execution

Numeric Constants

• Numeric values that have one value throughout the program execution

Level Number

• Is used to specify the level of data in a record

• Can be group or elementary items

Elementary items

• These items cannot be divided even further

• Level number, data name, Picture clause, and value clause are used to describe this

Group Items

• Consists of one or more elementary items

• The level number of this item is always 01

Picture clause

• Is used to describe the format and characteristics of a data item

• It tells the compiler what type of data will be stored and how it will be displayed

Data type

• Picture clause defines this whether it is numeric, alphabetic, or alphanumeric

Sign

• Whether the values can be positive or negative

Decimal point position

• Where the decimal is placed in numeric data

Length

• Refers to how many characters or digits are allowed

PIC

• Keyword for picture clause

X

• May contain any character including special or unprintable characters

9

• May contain only numeric characters from 0-9

A

• May only contain alphabetic characters from A-Z, a-z, and space

S

• Numeric sign

• Does not use any actual storage, without this character, a numeric item would be treated as unsigned

V

• Implied decimal Point

• It separates the integer portion of a numeric item from its decimal portion 

• Used to keep track of the decimal point for arithmetic calculations

P

• Numeric Placeholder

• Used to change the precision and can also be used to represent positions after the decimal

-

• Used to display a sign in a printed item

• This character will be showed if the numeric value is negative

+

• Used to display a sign in a printed item, it will be showed if the value is positive

.

• Actual decimal point

• Separates the integer portion of a numeric item from its decimal portion

• This character cannot be used in an item involved in calculations

Z

• Zero Suppress

• Replaces leading zeros with blanks, has no effect on non-zero positions or zero in not leading positions

,

• Commonly used as a separator in numeric data items

$

• Inserts a dollar sign into the first position in the data item

• Commonly used for currency but can also be used to suppress 0s

*

• Replaces leading zeros with asterisks

• Commonly used in check writing

CR

• Credit

• Used at the end of a PICTURE clause

• This will appear in the position indicated if the item is negative

DB

• Debit

• This will appear in the position indicated if the item is positive

/

• Commonly used as a separator in date fields

0

• Inserts a zero into the data item in this position

• Not commonly used

Value Clause

• It is an optional clause which is used to initialize the data items

• The values can be numeric, literal, alphanumeric literal, or figurative constant

Rounded clause

• Provides automatic rounding

On Size Error clause

• Is a conditional statement that implies “if there the size of a value does not fit in the field”, do whatever is indicated in the statement that follows the statement.

• The following statement must be imperative