TMF1013 : Introduction To Computing Lecture 1 : Fundamental of Computer ComputerFoudamentals

TMF1013 : Introduction To Computing Lecture 1 : Fundamental of Computer Computer is a device that can input and store a set of instructions designed to perform a specific task, input and store data, process the stored data according to the instructions, and produce output to be relayed to its user

TMF1013 : Introduction To Computing Lecture 1 : Fundamental of Computer Computer Software software is a synonym for program classify as applications software and systems software Applications software refers to programs that solve some specific problems Systems software refers to programs that make the computer usable and accessible to the developers and programmers of applications software

TMF1013 : Introduction To Computing Lecture 1 : Fundamental of Computer Operating System manages overall operation of the computer system OS Tasks validate user make others systems software available to users allocate memory and processor time to programs manage available secondary memory manage disk and tape file control various input & output Example : DOS, UNIX, GUI OS - Win95, Win NT..

TMF1013 : Introduction To Computing Lecture 1 : Fundamental of Computer Computer Programming Instructions given to the computer for problem solving in a particular programming language Programming refers to the creation of a list of stored instructions that tell the computer what to do When to write programs before, when the computer was needed for a job a lot of software available, if nothing available & suitable, programs will have to be written or existing software can be customized

TMF1013 : Introduction To Computing Lecture 1 : Fundamental of Computer Programming A program is a logical pattern of instructions to solve a problem steps define the problem develop an algorithm - define how the problem is to be solved do program coding by following the syntax of the progamming language test the program for logic errors and debug it for bugs prepare documentation which includes user instructions, an explanation of the logic of the program and information about the input and output

TMF1013 : Introduction To Computing Lecture 1 : Fundamental of Computer Programming Languages Is an artificial and formal language that has a limited vocabulary consisting of a set of keywords for making up instructions and a set of precise grammar rules. Programmers write computer instruction in programming languages, some directly understandable by one computer and others that require intermediate steps Different languages are used for different types of applications 3 main categories Machine language (1st generation) Assembly language (2nd generation) High level language

TMF1013 : Introduction To Computing Lecture 1 : Fundamental of Computer Machine Languages Is the natural language of a computer doesn’t need to be translated - immediate execution consists binary string 1s and 0s difficult to learn instruction corresponds to a basic capability of computer - simple problems require large numbers of instruction machine-dependent not portable

TMF1013 : Introduction To Computing Lecture 1 : Fundamental of Computer Assembly Languages Consist of English-like abbreviations that are less cryptic that machine language have to translated into machine language each computer type has its own assembly language L 1, GROSSPAY S 1, TAX ST 1, NETPAY

TMF1013 : Introduction To Computing Lecture 1 : Fundamental of Computer High-Level Languages Quite English-like a single instruction can be written to correspond to many operation at the machine level netpay = grosspay - tax; easy to learn have to be converted to machine languages portable FORTRAN, COBOL BASIC, Pascal 4th generation 5th generation

TMF1013 : Introduction To Computing Lecture 1 : Fundamental of Computer Natural languages ( 5th generation) resembles spoken English also referred as knowledge-based languages Language Translators a type of system software which includes assemblers, interpreters and compilers. The processes of translation to machine-readable code is different in each of these. Assemblers are translators that convert low-level assembly language to machine language compilers and interpreters translate high level language source code into machine language object code.

TMF1013 : Introduction To Computing Lecture 1 : Fundamental of Computer Compilers It translates the complete program all at one object code produced can be saved and run when needed Efficient - run programs after they are translated Interpreters translates each line of instruction as it goes through the program the object code produced cannot be saved program must be interpreted every time it is executed good for correcting programs but slower than compilers to run finished programs

TMF1013 : Introduction To Computing Lecture 1 : Fundamental of Computer Problem Solving is the process of transforming the description of a problem into the solution of that problem by using our knowledge of the problem domain and relying on our ability to select and use appropriate problem- solving strategies, techniques, and tools. An algorithm is a sequence of a finite number of steps arranged in a specific logical order, which, when executed, produce the solution for a problem

TMF1013 : Introduction To Computing Lecture 1 : Fundamental of Computer Pseudocode language is a semiformal, English-like language with a limited vocabulary that can be used to design and describe algorithm Flowcharting Flowchart is a graph consisting of geometrical shapes that are connected by flow lines the shapes represent the types of statements in an algorithm

TMF1013 : Introduction To Computing Lecture 1 : Fundamental of Computer Programming process Define the problem Planning the solution using flowchart,pseudocode, structure charts Coding the program using programming language Testing program desk-checking, debugging for error - syntax & logic error Documenting program description of programming life cycle program description, flowcharts and pseudocode,data….

TMF1013 : Introduction To Computing Lecture 1 : Fundamental of Computer Basic Control structure for pseudocode language sequence control structure selection control structure nested selection structure repetition control structure

TMF1013 : Introduction To Computing Lecture 1 : Fundamental of Computer Sequence Control Structure is a series of steps or statements that are executed in the order in which they are written in an algorithms. Example Read taxable income read filing status compute income tax print income tax

TMF1013 : Introduction To Computing Lecture 1 : Fundamental of Computer Selection Control Structure defines two course of action, depending on the outcome of a condition. A condition is an expression that, when evaluated, computes to either true or false. If condition then-part else else-part end_if

TMF1013 : Introduction To Computing Lecture 1 : Fundamental of Computer Nested Selected Structure is a basic selection structure that contains other if/else structures in its then-part or else-part if status is equal to 1 print “Single” else if status is equal to 2 ….

TMF1013 : Introduction To Computing Lecture 1 : Fundamental of Computer Repetition Control Structure Specifies a block of one or more statements that are repeatedly executed until a condition is satisfied While condition loop-body end_while

TMF1013 : Introduction To Computing Lecture 1 : Fundamental of Computer Conventions For Pseudocoding Each pseudocode statement includes keywords that describe operations and some appropriate, English like descriptions of operand. Should be written on a separate line. If a statement requires more than one line, the continuation lines should be indented should begin with unambiguous word such as compute, set and initialize. Statements in a sequence structure can be grouped into a block by enclosing them between the keywords begin and end For selection control structure, use an if/else statement. In an if/else statement, the then-part and, if used, the else-part should be indented. Terminate each if statement with keyword end_if For the repetition control structure, use the while statement and indent the loop-body. Termninate each while statement with the keyword end_while

TMF1013 : Introduction To Computing Lecture 1 : Fundamental of Computer What is pseudocode? Pseudocode consists of short, English phrases used to explain specific tasks within a program's algorithm. Pseudocode should not include keywords in any specific computer languages. It should be written as a list of consecutive phrases. You should not use flowcharting symbols but you can draw arrows to show loopingprocesses. Indentation can be used to show the logic in pseudocode as well. One programmer should be able to take another programmer's pseudocode and generate a program based on that pseudocode.

TMF1013 : Introduction To Computing Lecture 1 : Fundamental of Computer Why is pseudocode necessary? The programming process is a complicated one. You must first understand the program specifications, of course, Then you need to organize your thoughts and create the program. This is a difficult task when the program is not trivial (i.e. easy). You must break the main tasks that must be accomplished into smaller ones in order to be able to eventually write fully developed code. Writing pseudocode WILL save you time later during the construction & testing phase of a program's development.

TMF1013 : Introduction To Computing Lecture 1 : Fundamental of Computer How do I write pseudocode? First you may want to make a list of the main tasks that must be accomplished on a piece of scratch paper. Then, focus on each of those tasks. Generally, you should try to break each main task down into very small tasks that can each be explained with a short phrase. There may eventually be a one-to-one correlation between the lines of pseudocode and the lines of the code that you write after you have finished pseudocoding.