CS CS Computing for Business Instructor:David Tucker GTA:Batul Mirza

CS Overview of the Course Syllabus Use of computers in business Introduction to programming using COBOL

CS Brief Introduction to Computers Computer hardware  PC & components  Mainframes Computer software  Programs which cause a computer to carry out a task  Sequential instructions  Processes data  Examples Data  Raw fact Information  Organized and processed  Form that is meaningful

CS Types of Processing Batch processing  Submit a job – wait – get results  Ex. Monthly payroll processing  Posting to general the ledger  Validation checks Interactive processing  Interaction with a computer through a terminal  Personal computer

CS Business Data Processing COBOL : common business oriented language Characteristics of B.D.P.  Many large data files  Relatively few computations  Lots of reports Typical tasks of B.D.P.  Rearrange data  Change data’s appearance  Compare data items  Locate items  Summarize  Tabulate  Combine data

CS Algorithm A natural language statement of a systematic procedure for solving a problem. Algorithm Characteristics  Must terminate  Have zero or more inputs  Have one or more outputs  Each step unambiguous

CS Examples of Algorithms Add 2 numbers  Get num1  Get num2  Sum <- num1 + num2  Write sum Calculate Pay  Get rate of pay  Get hours worked  pay <- rate_of_pay * hours worked  Write pay

CS Languages Machine  0 & 1s only Low-level  Assembly  Managing memory High-level  COBOL, C, Pascal  Machine does the work of translating Natural language  English  Spanish

CS COBOL Features English-like Self-documenting “sort of” Data declaration “location”  File structure  Records Fixed decimal data handling Separates machine independent and machine dependant parts “Environment Division”

CS Data Organization Data is composed of 3 types of characters 1. Digits or numeric characters (0,1,…9) 2. Letters or alphabetic characters (A,B,…Z) 3. Special characters (coma, decimal point, equal sign, space, etc.) Field hold a piece of information  Alphanumeric field  Numeric field Record  Related fields File  Records that are used together

CS Programming Specifications Program name Narrative or additional info Input File(s) Input Record Layout  Fields in which location of the row Data Report Layout Processing Requirement  File  Filtering  Printing

CS Logic Write out the logic before you start coding  Pseudocode  Flow chart

CS Divisions of a COBOL Program 1. IDENTIFICATION DIVISION – provides basic information about the program such as a name 2. ENVIRONMENT DIVISION – Specifies the computer hardware that is to be used when the program is compiled and executed

CS Divisions Cont. DATA DIVISION – defines the characteristics of the files, records, and fields to be used in the program. File section FD (file description) SELECT statement Level numbers Relation to each other 01 – record description entry 05 – field entry Record description Working-storage section Define data that does not appear in the input or output.

CS Divisions Cont. PROCEDURE DIVISION – specifies the processing steps to be followed by the computer when the program is executed.  Paragraphs (procedures)  PERFORM statement  IF statement  READ statement Test data

CS Elements of COBOL Reserved words Programmer-supplied names  Paragraph names  Data names  File names Literals  Numeric  Non numeric Symbols  Punctuation  Arithmetic  Relational Level numbers Pictures